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  • 151.
    Al-Soubaihi, Rola
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Saoud, Khaled Mohammad
    Virginia Commonwealth Univ Qatar, Liberal Arts & Sci Program, POB 8095, Doha, Qatar..
    Dutta, Joydeep
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Low-temperature CO oxidation by silver nanoparticles in silica aerogel mesoreactors2023In: Chemical Engineering Journal, ISSN 1385-8947, E-ISSN 1873-3212, Vol. 455, p. 140576-, article id 140576Article in journal (Refereed)
    Abstract [en]

    Low-temperature carbon monoxide (CO) oxidation on silver/silica aerogel (Ag/SiO2 AG) catalyst prepared by one-pot sol-gel synthesis followed by supercritical ethanol drying method is reported. Highly stable and sinterproof catalyst led to easy reactant diffusion to the active sites. The Ag/SiO2 AG catalyst showed enhanced catalytic activity toward low-temperature CO oxidation by preventing agglomeration of silver nanoparticles inside pores and facilitating well-dispersed active sites to enhance the mass heat transfer in the mesopores. Catalyst pretreatment conditions were found to play a crucial role in achieving high CO conversion efficiency at low light-off temperatures. Inverse counter-clockwise CO oxidation hysteresis was found to occur after the first run. The active sites contributing to this enhanced catalytic behavior were confirmed to be Ag0 from XPS, XRD, and TEM analysis. The catalyst exhibited good thermal stability up to 450 degrees C over repeated number of cycles.

  • 152.
    Alsufyani, Maryam
    et al.
    King Abdullah Univ Sci & Technol KAUST, Saudi Arabia.
    Hallani, Rawad K.
    King Abdullah Univ Sci & Technol KAUST, Saudi Arabia.
    Wang, Suhao
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Xiao, Mingfei
    Univ Cambridge, England.
    Ji, Xudong
    Northwestern Univ, IL 60208 USA.
    Paulsen, Bryan D.
    Northwestern Univ, IL 60208 USA.
    Xu, Kai
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Bristow, Helen
    Univ Cambridge, England.
    Chen, Hu
    King Abdullah Univ Sci & Technol KAUST, Saudi Arabia.
    Chen, Xingxing
    King Abdullah Univ Sci & Technol KAUST, Saudi Arabia.
    Sirringhaus, Henning
    King Abdullah Univ Sci & Technol KAUST, Saudi Arabia.
    Rivnay, Jonathan
    Northwestern Univ, IL 60208 USA.
    Fabiano, Simone
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    McCulloch, Iain
    King Abdullah Univ Sci & Technol KAUST, Saudi Arabia; Univ Oxford, England.
    The effect of aromatic ring size in electron deficient semiconducting polymers for n-type organic thermoelectrics2020In: Journal of Materials Chemistry C, ISSN 2050-7526, E-ISSN 2050-7534, Vol. 8, no 43, p. 15150-15157Article in journal (Refereed)
    Abstract [en]

    N-type semiconducting polymers have been recently utilized in thermoelectric devices, however they have typically exhibited low electrical conductivities and poor device stability, in contrast to p-type semiconductors, which have been much higher performing. This is due in particular to the n-type semiconductors low doping efficiency, and poor charge carrier mobility. Strategies to enhance the thermoelectric performance of n-type materials include optimizing the electron affinity (EA) with respect to the dopant to improve the doping process and increasing the charge carrier mobility through enhanced molecular packing. Here, we report the design, synthesis and characterization of fused electron-deficient n-type copolymers incorporating the electron withdrawing lactone unit along the backbone. The polymers were synthesized using metal-free aldol condensation conditions to explore the effect of enlarging the central phenyl ring to a naphthalene ring, on the electrical conductivity. When n-doped with N-DMBI, electrical conductivities of up to 0.28 S cm(-1), Seebeck coefficients of -75 mu V K-1 and maximum Power factors of 0.16 mu W m(-1) K-2 were observed from the polymer with the largest electron affinity of -4.68 eV. Extending the aromatic ring reduced the electron affinity, due to reducing the density of electron withdrawing groups and subsequently the electrical conductivity reduced by almost two orders of magnitude.

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  • 153.
    Alsufyani, Maryam
    et al.
    Univ Oxford, England.
    Stoeckel, Marc-Antoine
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Chen, Xingxing
    King Abdullah Univ Sci & Technol KAUST, Saudi Arabia.
    Thorley, Karl
    Univ Kentucky, KY 40506 USA.
    Hallani, Rawad K.
    King Abdullah Univ Sci & Technol KAUST, Saudi Arabia.
    Puttisong, Yuttapoom
    Linköping University, Department of Physics, Chemistry and Biology, Electronic and photonic materials. Linköping University, Faculty of Science & Engineering.
    Ji, Xudong
    Northwestern Univ, IL 60208 USA.
    Meli, Dilara
    Northwestern Univ, IL 60208 USA.
    Paulsen, Bryan D.
    Northwestern Univ, IL 60208 USA.
    Strzalka, Joseph
    Argonne Natl Lab, IL 60439 USA.
    Regeta, Khrystyna
    King Abdullah Univ Sci & Technol KAUST, Saudi Arabia.
    Combe, Craig
    King Abdullah Univ Sci & Technol KAUST, Saudi Arabia.
    Chen, Hu
    King Abdullah Univ Sci & Technol KAUST, Saudi Arabia.
    Tian, Junfu
    Univ Oxford, England.
    Rivnay, Jonathan
    Northwestern Univ, IL 60208 USA; Northwestern Univ, IL 60611 USA.
    Fabiano, Simone
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    McCulloch, Iain
    Univ Oxford, England; King Abdullah Univ Sci & Technol KAUST, Saudi Arabia.
    Lactone Backbone Density in Rigid Electron-Deficient Semiconducting Polymers Enabling High n-type Organic Thermoelectric Performance2022In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 61, no 7, article id e202113078Article in journal (Refereed)
    Abstract [en]

    Three lactone-based rigid semiconducting polymers were designed to overcome major limitations in the development of n-type organic thermoelectrics, namely electrical conductivity and air stability. Experimental and theoretical investigations demonstrated that increasing the lactone group density by increasing the benzene content from 0 % benzene (P-0), to 50 % (P-50), and 75 % (P-75) resulted in progressively larger electron affinities (up to 4.37 eV), suggesting a more favorable doping process, when employing (N-DMBI) as the dopant. Larger polaron delocalization was also evident, due to the more planarized conformation, which is proposed to lead to a lower hopping energy barrier. As a consequence, the electrical conductivity increased by three orders of magnitude, to achieve values of up to 12 S cm and Power factors of 13.2 mu Wm(-1) K-2 were thereby enabled. These findings present new insights into material design guidelines for the future development of air stable n-type organic thermoelectrics.

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  • 154.
    Alterby, Malin
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Johnson, Emily
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Jonason, Anton
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Svensson, Denize
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    3D Printing Hydrogel Artificial Muscles and Microrobotics2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this lab was to investigate the printability of cellulose nanofiber/carbon nanotubes, their functions as actuators, and to compare these properties with MXene/nano cellulose gels. Data on MXene/nano cellulose gel was obtained from previous research made by Hamedi labs. Data on carbon nanotubes were collected through experiments evaluating different concentrations and sonication times to yield a gel with high conductivity and viscosity. While it was concluded that both gels could be printed into 2D or 3D shapes, the latter failed to maintain its structure over time due to issues with drying. However, it was found that only 2D MXene/CNF could be used as a reversible actuator.

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  • 155.
    Alvarado Ávila, María Isabel
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics. KTH, School of Biotechnology (BIO), Centres, Albanova VinnExcellence Center for Protein Technology, ProNova.
    Toledo-Carrillo, Esteban Alejandro
    KTH, School of Biotechnology (BIO), Centres, Albanova VinnExcellence Center for Protein Technology, ProNova. KTH, School of Engineering Sciences (SCI), Applied Physics.
    Dutta, Joydeep
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics. KTH, School of Biotechnology (BIO), Centres, Albanova VinnExcellence Center for Protein Technology, ProNova.
    Improved chlorate production with platinum nanoparticles deposited on fluorinated activated carbon cloth electrodes2020In: Cleaner Engineering and Technology, ISSN 2666-7908, Vol. 1, article id 100016Article in journal (Refereed)
    Abstract [en]

    Sodium chlorate is one of the main oxidizing agents used in the wood industry due to their capability of use as an elemental chlorine-free (CEF) bleaching. A simple way to produce chlorates is by the electrolysis of an aqueous sodium chloride (NaCl) solution. In the present study activated carbon cloth electrodes (ACC) modified with fluorine and platinum nanoparticles (Pt–F/ACC and Pt/ACC) were used as one of the electrodes. Electrofluorination was used for fluorination of the anodes and polyol method was used for the synthesis of platinum nanoparticles. Chlorate production using a typical solution of 100 ​g/l of sodium chloride (NaCl) and 2 ​g/l sodium chromate (Na2Cr2O7) and an applied current of 0.540 ​A was studied. Prior to the electrolysis assays, the microstructural properties of the electrodes were characterized by scanning electron microscopy and surface modifications and bonding using infra-red (FTIR) spectroscopy. Electrochemical properties were determined using cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. Interaction between fluorine (F) and platinum (Pt) on the electrode leads to an improvement of the electrocatalytic properties for chlorine evolution as observed from the increase in the current efficiency from 37.5% at 78.5% after 150 ​min of continuous electrolysis using Pt–F/ACC anodes. The results suggest that modified activated carbon material is an attractive and economical alternative as electrodes for chlorate production. 

  • 156.
    Alvarez, Sol Gutierrez
    et al.
    Tech Univ Denmark, Dept Chem, DK-2800 Lyngby, Denmark..
    Lin, Weihua
    Lund Univ, Dept Chem Phys, S-22100 Lund, Sweden.;Lund Univ, NanoLund Chem Ctr, S-22100 Lund, Sweden..
    Abdellah, Mohamed
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Meng, Jie
    Tech Univ Denmark, Dept Chem, DK-2800 Lyngby, Denmark..
    Zidek, Karel
    Czech Acad Sci, Vvi, Inst Plasma Phys, Res Ctr Special Opt & Optoelect Syst TOPTEC, Prague 18200 8, Czech Republic..
    Pullerits, Tönu
    Lund Univ, Dept Chem Phys, S-22100 Lund, Sweden.;Lund Univ, NanoLund Chem Ctr, S-22100 Lund, Sweden..
    Zheng, Kaibo
    Tech Univ Denmark, Dept Chem, DK-2800 Lyngby, Denmark.;Lund Univ, Dept Chem Phys, S-22100 Lund, Sweden.;Lund Univ, NanoLund Chem Ctr, S-22100 Lund, Sweden..
    Charge Carrier Diffusion Dynamics in Multisized Quaternary Alkylammonium-Capped CsPbBr3 Perovskite Nanocrystal Solids2021In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 13, no 37, p. 44742-44750Article in journal (Refereed)
    Abstract [en]

    CsPbBr3 quantum dots (QDs) are promising candidates for optoelectronic devices. The substitution of oleic acid ( OA) and oleylamine ( OLA) capping agents with a quaternary alkylammonium such as di-dodecyl dimethyl ammonium bromide (DDAB) has shown an increase in external quantum efficiency (EQE) from 0.19% (OA/OLA) to 13.4% (DDAB) in LED devices. The device performance significantly depends on both the diffusion length and the mobility of photoexcited charge carriers in QD solids. Therefore, we investigated the charge carrier transport dynamics in DDAB-capped CsPbBr3 QD solids by constructing a bi-sized QD mixture film. Charge carrier diffusion can be monitored by quantitatively varying the ratio between two sizes of QDs, which varies the mean free path of the carriers in each QD cluster. Excited-state dynamics of the QD solids obtained from ultrafast transient absorption spectroscopy reveals that the photogenerated electrons and holes are difficult to diffuse among small-sized QDs (4 nm) due to the strong quantum confinement. On the other hand, both photoinduced electrons and holes in large-sized QDs (10 nm) would diffuse toward the interface with the small-sized QDs, followed by a recombination process. Combining the carrier diffusion study with a Monte Carlo simulation on the QD assembly in the mixture films, we can calculate the diffusion lengths of charge carriers to be similar to 239 +/- 16 nm in 10 nm CsPbBr3 QDs and the mobility values of electrons and holes to be 2.1 (+/- 0.1) and 0.69 (+/- 0.03) cm(2)/V s, respectively. Both parameters indicate an efficient charge carrier transport in DDAB-capped QD films, which rationalized the perfect performance of their LED device application.

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  • 157.
    Alvi, Sajid
    et al.
    Department of Physics, Chalmers University of Technology, Chalmersplatsen 4, 412 96, Göteborg, Sweden.
    Black, Ashley P.
    Institut de Ciència de Materials de Barcelona, ICMAB-CSIC Campus UAB, 08193, Bellaterra, Catalonia, Spain.
    Jozami, Ignacio
    Department of Physics, Chalmers University of Technology, Chalmersplatsen 4, 412 96, Göteborg, Sweden.
    Escudero, Carlos
    NOTOS, ALBA Synchrotron, Cerdanyola del Vallès, 08193, Catalonia, Spain.
    Akhtar, Farid
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Johansson, Patrik
    Department of Physics, Chalmers University of Technology, Chalmersplatsen 4, 412 96, Göteborg, Sweden; ALISTORE-ERI, CNRS FR 3104, Hub de I'Energie, 80039, Amiens Cedex, France.
    Entropy Stabilized Medium High Entropy Alloy Anodes for Lithium-ion Batteries2024In: Batteries & Supercaps, E-ISSN 2566-6223Article in journal (Refereed)
    Abstract [en]

    One often proposed route to improved energy density for lithium-ion batteries is to use alloy anodes, such as silicon, able to store large amounts of lithium. Mechanical instability caused by the large expansion and contraction associated with (de)lithiation, and hence bad cyclability, has, however, so far hindered progress. As proof-of-concept of a remedy, we here present BiSbSe1.5Te1.5, a medium high-entropy alloy with improved cycling stability for conversion-alloying (de)lithiation reactions. We attain five to twenty times more stable cycles than previously reported for comparable metal-Se and -Te-based anodes, with a very good reversible capacity (464 mAh g−1) for up to 110 cycles- and this without using any carbonaceous materials to create a composite. Altogether, this highlights how alloy engineering and increased entropy materials can stabilize conversion-alloying electrodes.

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  • 158.
    Alvi, Sajid
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Department of Physics, Chalmers University of Technology, SE‐412 96 Göteborg, Sweden.
    Milczarek, Michal
    Department of Mechanics of Materials (ZMM), Institute of Fundamental Technological Research, Polish Academy of Sciences, 02-106 Warsaw, Poland.
    Jarzabek, Dariusz M.
    Department of Mechanics of Materials (ZMM), Institute of Fundamental Technological Research, Polish Academy of Sciences, 02-106 Warsaw, Poland.
    Hedman, Daniel
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Research Center for Computational Design of Advanced Functional Materials, National Institute of Advanced Industrial Science and Technology (AIST), Central 2, 1‐1‐1 Umezono, Tsukuba, Ibaraki, 305‐8568 Japan; Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan, 44919 Republic of Korea.
    Gilzad Kohan, Mojtaba
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Levintant-Zayonts, Neonila
    Department of Mechanics of Materials (ZMM), Institute of Fundamental Technological Research, Polish Academy of Sciences, 02-106 Warsaw, Poland.
    Vomiero, Alberto
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, Via Torino 155, 30172 Mestre Venezia, Italy.
    Akhtar, Farid
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Enhanced mechanical, thermal and electrical properties of high‐entropy HfMoNbTaTiVWZr thin film metallic glass and its nitrides2022In: Advanced Engineering Materials, ISSN 1438-1656, E-ISSN 1527-2648, Vol. 24, no 9, article id 2101626Article in journal (Refereed)
    Abstract [en]

    The inception of high-entropy alloy promises to push the boundaries for new alloy design with unprecedented properties. This work reports entropy stabilisation of an octonary refractory, HfMoNbTaTiVWZr, high-entropy thin film metallic glass, and derived nitride films. The thin film metallic glass exhibited exceptional ductility of ≈60% strain without fracture and compression strength of 3 GPa in micro-compression, due to the presence of high density and strength of bonds. The thin film metallic glass shows thermal stability up to 750 °C and resistance to Ar-ion irradiation. Nitriding during film deposition of HfMoNbTaTiVWZr thin film of strong nitride forming refractory elements results in deposition of nanocrystalline nitride films with compressive strength, hardness, and thermal stability of up to 10 GPa, 18.7 GPa, and 950 °C, respectively. The high amount of lattice distortion in the nitride films leads to its insulating behaviour with electrical conductivity as low as 200 S cm−1 in the as-deposited film. The design and exceptional properties of the thin film metallic glass and derived nitride films may open up new avenues of development of bulk metallic glasses and the application of refractory-based high entropy thin films in structural and functional applications.

  • 159.
    Amagat, Jordi
    et al.
    Aarhus Univ, Dept Biol & Chem Engn, Aarhus, Denmark.;Univ Chinese Acad Sci, Sinodanish Coll SDC, Beijing 101400, Peoples R China..
    Su, Yingchun
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electronics and Embedded systems, Electronic and embedded systems. Aarhus Univ, Dept Biol & Chem Engn, Aarhus, Denmark..
    Svejso, Frederik Hobjerg
    Aarhus Univ, Dept Biol & Chem Engn, Aarhus, Denmark..
    Le Friec, Alice
    Aarhus Univ, Dept Biol & Chem Engn, Aarhus, Denmark..
    Sonderskov, Steffan Moller
    Aarhus Univ, INANO, Interdisciplinary Nanosci Ctr, Aarhus, Denmark..
    Dong, Mingdong
    Aarhus Univ, INANO, Interdisciplinary Nanosci Ctr, Aarhus, Denmark..
    Fang, Ying
    Chinese Acad Sci, Ctr Excellence Nanosci, Natl Ctr Nanosci & Technol, Beijing 100190, Peoples R China.;Chinese Acad Sci, Inst Neurosci, CAS Ctr Excellence Brain Sci & Intelligence Techno, Shanghai 200031, Peoples R China..
    Chen, Menglin
    Aarhus Univ, Dept Biol & Chem Engn, Aarhus, Denmark.;Aarhus Univ, INANO, Interdisciplinary Nanosci Ctr, Aarhus, Denmark.;Aarhus Univ, Univ Byen 36, DK-8000 Aarhus, Denmark..
    Self-snapping hydrogel-based electroactive microchannels as nerve guidance conduits2022In: MATERIALS TODAY BIO, ISSN 2590-0064, Vol. 16, article id 100437Article in journal (Refereed)
    Abstract [en]

    Peripheral nerve regeneration with large defects needs innovative design of nerve guidance conduits (NGCs) which possess anisotropic guidance, electrical induction and right mechanical properties in one. Herein, we present, for the first time, facile fabrication and efficient neural differentiation guidance of anisotropic, conductive, self-snapping, hydrogel-based NGCs. The hydrogels were fabricated via crosslinking of graphitic carbon nitride (g-C3N4) upon exposure with blue light, incorporated with graphene oxide (GO). Incorporation of GO and in situ reduction greatly enhanced surface charges, while decayed light penetration endowed the hydrogel with an intriguing self-snapping feature by the virtue of a crosslinking gradient. The hydrogels were in the optimal mechanical stiffness range for peripheral nerve regeneration and supported normal viability and proliferation of neural cells. The PC12 cells differentiated on the electroactive g-C3N4 H/rGO3 (3 mg/mL GO loading) hydrogel presented 47% longer neurite length than that of the pristine g-C3N4 H hydrogel. Furthermore, the NGC with aligned microchannels was successfully fabricated using sacrificial melt electrowriting (MEW) moulding, the anisotropic microchannels of the 10 mu m width showed optimal neurite guidance. Such anisotropic, electroactive, self-snapping NGCs may possess great potential for repairing peripheral nerve injuries.

  • 160.
    Amin, Sidra
    et al.
    Lulea Univ Technol, Sweden; Shaheed Benazir Bhutto Univ, Pakistan.
    Tahira, Aneela
    Lulea Univ Technol, Sweden.
    Solangi, Amber
    Univ Sindh, Pakistan.
    Beni, Valerio
    Res Inst Sweden, Sweden.
    Morante, J. R.
    Catalonia Inst Energy Res IREC, Spain.
    Liu, Xianjie
    Linköping University, Department of Physics, Chemistry and Biology, Surface Physics and Chemistry. Linköping University, Faculty of Science & Engineering.
    Fahlman, Mats
    Linköping University, Department of Physics, Chemistry and Biology, Surface Physics and Chemistry. Linköping University, Faculty of Science & Engineering.
    Mazzaro, Raffaello
    Lulea Univ Technol, Sweden.
    Ibupoto, Zafar Hussain
    Lulea Univ Technol, Sweden; Univ Sindh, Pakistan.
    Vomiero, Alberto
    Lulea Univ Technol, Sweden.
    A practical non-enzymatic urea sensor based on NiCo2O4 nanoneedles2019In: RSC Advances, E-ISSN 2046-2069, Vol. 9, no 25, p. 14443-14451Article in journal (Refereed)
    Abstract [en]

    We propose a new facile electrochemical sensing platform for determination of urea, based on a glassy carbon electrode (GCE) modified with nickel cobalt oxide (NiCo2O4) nanoneedles. These nanoneedles are used for the first time for highly sensitive determination of urea with the lowest detection limit (1 mu M) ever reported for the non-enzymatic approach. The nanoneedles were grown through a simple and low-temperature aqueous chemical method. We characterized the structural and morphological properties of the NiCo2O4 nanoneedles by TEM, SEM, XPS and XRD. The bimetallic nickel cobalt oxide exhibits nanoneedle morphology, which results from the self-assembly of nanoparticles. The NiCo2O4 nanoneedles are exclusively composed of Ni, Co, and O and exhibit a cubic crystalline phase. Cyclic voltammetry was used to study the enhanced electrochemical properties of a NiCo2O4 nanoneedle-modified GCE by overcoming the typical poor conductivity of bare NiO and Co3O4. The GCE-modified electrode is highly sensitive towards urea, with a linear response (R-2 = 0.99) over the concentration range 0.01-5 mM and with a detection limit of 1.0 mu M. The proposed non-enzymatic urea sensor is highly selective even in the presence of common interferents such as glucose, uric acid, and ascorbic acid. This new urea sensor has good viability for urea analysis in urine samples and can represent a significant advancement in the field, owing to the simple and cost-effective fabrication of electrodes, which can be used as a promising analytical tool for urea estimation.

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  • 161.
    Amin, Sidra
    et al.
    Univ Sindh, Pakistan; Shaheed Benazir Bhutto Univ, Pakistan.
    Tahira, Aneela
    Linköping University, Department of Science and Technology, Physics, Electronics and Mathematics. Linköping University, Faculty of Science & Engineering.
    Solangi, Amber
    Univ Sindh, Pakistan.
    Nafady, Ayman
    King Saud Univ, Saudi Arabia.
    Ibupoto, Zafar Hussain
    Univ Sindh, Pakistan.
    MoSx-Co3O4 Nanocomposite for Selective Determination of Ascorbic Acid2021In: Journal of Nanoscience and Nanotechnology, ISSN 1533-4880, E-ISSN 1533-4899, Vol. 21, no 4, p. 2595-2603Article in journal (Refereed)
    Abstract [en]

    Designing a nanocomposite with sensitive and selective determination of ascorbic acid is challenging task. It is possible through the exploitation of attractive features of nanoscience and nanotechnology for the synthesis of nanostructured materials. Herein, we report the decoration of nanoparticle of MoSx on the surface of Co3O4 nanowires by hydrothermal method. The MoSx nanoparticles shared the large surface on the Co3O4 nanowires, thus it supported in the development enzyme free ascorbic acid sensor. Non-enzymatic sensor based on MoSx-Co3O4 composite was found very selective for the determination of ascorbic acid (AA) in phosphate buffer solution of pH 7.4. The MoSx-Co3O4 nanocomposite was used to modify the glassy carbon electrode to measure AA from variety of practical samples. The MoSx-Co3O4 nanocomposite was used to modify the glassy carbon electrode and it has shown the attractive analytical features such as a low working potential +0.3 V, linear range of concentration from 100-7000 mu M, low limit of detection 14 mu M, and low limit of quantification (LOQ) of 42 mu M. The developed sensor is highly selective and stable. Importantly, it was applied successfully for the practical applications such as detection of AA from grapefruit, tomato and lemon juice. The excellent electrochemical properties of fabricated MoSx-Co3O4 nanocomposite can be attributed to the increasing electro active surface area of MoSx. The presented nanocomposite is earth abundant, environment friendly and inexpensive and it holds promising features for the selective and sensitive determination of AA from practical applications. The nanocomposite can be capitalized into the wide range of biomedical applications.

  • 162.
    Amizhtan, S. K.
    et al.
    Indian Inst Technol Madras IIT Madras, Dept Elect Engn, Chennai 600036, India..
    Sarathi, R.
    Indian Inst Technol Madras IIT Madras, Dept Elect Engn, Chennai 600036, India..
    Edin, Hans Ezz
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electromagnetic Engineering and Fusion Science.
    Taylor, Nathaniel
    KTH, School of Electrical Engineering and Computer Science (EECS), Electrical Engineering, Electromagnetic Engineering and Fusion Science.
    Study on Conduction Mechanism in Corrosive Transformer Oil and its Reclamation Properties2023In: IEEE transactions on dielectrics and electrical insulation, ISSN 1070-9878, E-ISSN 1558-4135, Vol. 30, no 5, p. 2232-2239Article in journal (Refereed)
    Abstract [en]

    This work deals with the effect of oil reclamation on the conduction mechanism and dielectric aspects of accelerated thermally aged transformer mineral oil. The reclamation is a treatment with Fuller's earth (FE) adsorbent to remove corrosive sulfur compounds and other contaminants formed during thermal aging. The properties of the oil are compared between different stages of the treatment. Corona (partial discharge) inception is identified by the optical fluorescent fiber technique. The results show an increased corona inception voltage after treatment. Dielectric response spectroscopy (DRS) showed a lower loss factor and electrical conductivity after treatment. The conduction mechanism is measured under uniform and nonuniform electric fields with variations in applied voltage magnitude. The conduction mechanism at a uniform electric field (low E) is studied using the polarity reversal technique to estimate the respective ionic motilities in the fluid. The apparent mobility of ions, conductivity, ionic radius, and concentration from the oil are found to reduce on reclamation. In addition, the conduction mechanism for a higher electric field is simulated by the current-voltage characteristic in nonuniform conditions and the slope determines the ionic mobility of the fluid.

  • 163.
    Ammothum Kandy, Akshay Krishna
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Linear models for multiscale materials simulations: Towards a seamless linking of electronic and atomistic models for complex metal oxides2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Multiscale modelling approaches, connecting data from electronic structure calculations all the way towards engineering continuum models, have become an important ingredient in modern materials science. Materials modelling in a broader sense is already amply used to address complex chemical problems in academic science, but also in many industrial sectors. As far as multiscale modelling is concerned, however, many challenges remain, in particular when it comes to coupling and linking the various levels along the multiscale ladder in a seamless and efficient fashion.        

    This thesis focusses on the development of new and efficient linear models to improve the quality and parameterisation processes of the two-body potentials used in empirical and semi-empirical methods within a multiscale materials modelling framework. In this regard, a machinery called curvature constrained splines (CCS) based on cubic splines to approximate general two-body potentials has been developed. The method is linear, and parameters can be easily solved in a least-square sense using a quadratic programming approach. Moreover, the objective function is  convex, implying that global minima can be readily found. This makes the optimisation process easy to handle and requires little to no human effort. Initial tests to validate the method were performed on molecular and bulk neon systems. Later, the method was extended to incorporate long-range interactions by including atomic charges. The capability of the method was demonstrated for ZnO polymorphs, and at the same time benchmarked towards the conventional  Buckingham potentials applied to the same problem. The results indicate that the CCS+Q method performs on par with the Buckingham approach, but is much faster and easier to parameterise. The merits of the method is further demonstrated with an exploration of size and shape dependent stability of CeO2 nanoparticles.

    Having established the framework of the CCS methodology, the method was further used to develop repulsive potentials for the semi-empirical self-consistent charge density functional tight binding (SCC-DFTB) method. The generation of the repulsive potentials is normally a tedious and time-consuming task. The  CCS methodology  makes this process significantly more efficient, and further provides new opportunities to explore the limits of the SCC-DFTB method. The development of repulsive potentials for bulk Si polymorphs showed that it is possible to retrieve a good description of each individual polymorph, but impossible to obtain an acceptable joint description of all polymorphs. The results indicated that a transferable repulsive potential needs to have coordination dependence, and by the  use of a many-body artificial neural network representation for the repulsive potential, it was indeed possible to obtain a global transferability. The CCS methodology was finally used to model a system of considerable chemical diversity and complexity, namely reduced CeO2 within the SCC-DFTB formalism. Here, the CCS framework facilitated the development of an efficient workflow that yielded a harmonized description of Ce ions in different oxidation states. In short, the introduced CCS-based workflow proved to extend the applicability of SCC-DFTB to complex oxide systems with correlated electronic states.               

    To conclude, the CCS methodology is demonstrated to be a versatile tool for efficient linking between (and within) electronic and atomistic models.

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  • 164.
    Ammothum Kandy, Akshay Krishna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Wadbro, Eddie
    Aradi, Bálint
    Broqvist, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Kullgren, Jolla
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Curvature Constrained Splines for DFTB Repulsive Potential Parametrization2021In: Journal of Chemical Theory and Computation, ISSN 1549-9618, E-ISSN 1549-9626, Vol. 17, no 3, p. 1771-1781Article in journal (Refereed)
    Abstract [en]

    The Curvature Constrained Splines (CCS) methodology has been used for fitting repulsive potentials to be used in SCC-DFTB calculations. The benefit of using CCS is that the actual fitting of the repulsive potential is performed through quadratic programming on a convex objective function. This guarantees a unique (for strictly convex) and optimum two-body repulsive potential in a single shot, thereby making the parametrization process robust, and with minimal human effort. Furthermore, the constraints in CCS give the user control to tune the shape of the repulsive potential based on prior knowledge about the system in question. Herein, we developed the method further with new constraints and the capability to handle sparse data. We used the method to generate accurate repulsive potentials for bulk Si polymorphs and demonstrate that for a given Slater-Koster table, which reproduces the experimental band structure for bulk Si in its ground state, we are unable to find one single two-body repulsive potential that can accurately describe the various bulk polymorphs of silicon in our training set. We further demonstrate that to increase transferability, the repulsive potential needs to be adjusted to account for changes in the chemical environment, here expressed in the form of a coordination number. By training a near-sighted Atomistic Neural Network potential, which includes many-body effects but still essentially within the first-neighbor shell, we can obtain full transferability for SCC-DFTB in terms of describing the energetics of different Si polymorphs.

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  • 165.
    Amombo Noa, Francoise M.
    et al.
    Chalmers Univ Technol, Dept Chem & Chem Engn, Div Chem & Biochem, S-41296 Gothenburg, Sweden..
    Abrahamsson, Maria
    Chalmers Univ Technol, Dept Chem & Chem Engn, Div Chem & Biochem, S-41296 Gothenburg, Sweden..
    Ahlberg, Elisabet
    Univ Gothenburg, Dept Chem & Mol Biol, S-40530 Gothenburg, Sweden..
    Cheung, Ocean
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Nanotechnology and Functional Materials.
    Göb, Christian R.
    Rigaku Europe SE, Hugenottenallee 167, D-63263 Neu Isenburg, Germany..
    McKenzie, Christine J.
    Univ Southern Denmark, Dept Phys Chem & Pharm, Campusvej 55, DK-5230 Odense M, Denmark..
    Öhrström, Lars
    Chalmers Univ Technol, Dept Chem & Chem Engn, Div Chem & Biochem, S-41296 Gothenburg, Sweden..
    A unified topology approach to dot-, rod-, and sheet-MOFs2021In: Chem, ISSN 2451-9308, E-ISSN 2451-9294, Vol. 7, no 9, p. 2491-2512Article in journal (Refereed)
    Abstract [en]

    Metal-organic frameworks made from multi-metal-ion units in the shape of clusters and rods (termed dot-MOFs and rod-MOFs) are well known. Here, we introduce MOFs with multi-metallic units in the form of sheets—sheet-MOFs. We show exemplars of all three types of units based on structures containing Y3+, Ce3+, or Gd3+ linked by benzene-1,2,4,5-tetracarboxylate to give crystals of a dot-MOF in H2NMe2[Y(btec)(H2O)] CTH-14, a sheet-MOF in [Ce3(btec)(Hbtec)(OAc)(HCO2)] CTH-15, and a rod-MOF in 4,4′-azopyridinium[Gd2(btec)2] CTH-16. Cyclic voltammetry shows that CTH-15 stabilizes Ce(IV). Given the fact that sheet-MOFs represent an intellectual advance in the evolution of MOFs, a unified approach is proposed for the topological classification of dot-, rod-, and sheet-MOFs. It is suggested that the stability of MOFs follow in the trend dot < rod < sheet. For CTH-14-16, the sheet- and the rod-MOF have higher thermal stability. We suggest sheet-MOFs as an additional strategy for making robust MOFs.

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  • 166.
    Amombo Noa, Francoise M.
    et al.
    Chalmers Univ Technol, Dept Chem & Chem Engn, Chem & Biochem, SE-41296 Gothenburg, Sweden.
    Svensson Grape, Erik
    Stockholm Univ, Dept Mat & Environm Chem, SE-10691 Stockholm, Sweden.
    Brülls, Steffen Marc
    Chalmers Univ Technol, Dept Chem & Chem Engn, Chem & Biochem, SE-41296 Gothenburg, Sweden.
    Cheung, Ocean
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Nanotechnology and Functional Materials.
    Malmberg, Per
    Chalmers Univ Technol, Dept Chem & Chem Engn, Chem & Biochem, SE-41296 Gothenburg, Sweden.
    Inge, A. Ken
    Stockholm Univ, Dept Mat & Environm Chem, SE-10691 Stockholm, Sweden.
    McKenzie, Christine J.
    Univ Southern Denmark, Dept Phys Chem & Pharm, DK-5230 Odense M, Denmark.
    Mårtensson, Jerker
    Chalmers Univ Technol, Dept Chem & Chem Engn, Chem & Biochem, SE-41296 Gothenburg, Sweden.
    Öhrström, Lars
    Chalmers Univ Technol, Dept Chem & Chem Engn, Chem & Biochem, SE-41296 Gothenburg, Sweden.
    Metal-Organic Frameworks with Hexakis(4-carboxyphenyl)benzene: Extensions to Reticular Chemistry and Introducing Foldable Nets2020In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 142, no 20, p. 9471-9481Article in journal (Refereed)
    Abstract [en]

    Nine metal–organic frameworks have been prepared with the hexagon-shaped linker 1,2,3,4,5,6-hexakis(4-carboxyphenyl)benzene (H6cpb) by solvothermal reactions in dimethylformamide (dmf) or dimethylacetamide (dmac) with acetic acid or formic acid as modulators: [Bi2(cpb)(acetato)2(dmf)2]·2dmf CTH-6 forms a rtl-net; 2(H2NMe2)[Cu2(cpb)] CTH-7 forms a kgd-net; [Fe4(cpb)(acetato)2(dmf)4] CTH-8 and [Co4(cpb)(acetato)2(dmf)4] CTH-9 are isostructural and form yav-nets; 2(HNEt3)[Fe2(cpb)] CTH-10 and the two polymorphs of 2(H2NMe2)[Zn2(cpb)]·1.5dmac, Zn-MOF-888 and CTH-11, show kgd-nets; [Cu2(cpb)(acetato)2(dmf)2]·2dmf, CTH-12, forms a mixed coordination and hydrogen-bonded sql-net; and 2(H2NMe2)[Zn2(cpb)] CTH-13, a similarly mixed yav-net. Surface area values (Brunauer–Emmett–Teller, BET) range from 34 m2 g–1 for CTH-12 to 303 m2 g–1 for CTH-9 for samples activated at 120 °C in dynamic vacuum. All compounds show normal (10-fold higher) molar CO2 versus N2 uptake at 298 K, except the 19-fold CO2 uptake for CTH-12 containing Cu(II) dinuclear paddle-wheels. We also show how perfect hexagons and triangles can combine to a new 3D topology laf, a model of which gave us the idea of foldable network topologies, as the laf-net can fold into a 2D form while retaining the local geometry around each vertex. Other foldable nets identified are cds, cds-a, ths, sqc163, clh, jem, and tfc covering the basic polygons and their combinations. The impact of this concept on “breathing” MOFs is discussed. I2 sorption, both from gas phase and from MeOH solution, into CTH-7 were studied by time of flight secondary ion mass spectrometry (ToF-SIMS) on dried crystals. I2 was shown to have penetrated the crystals, as layers were consecutively peeled off by the ion beam. We suggest ToF-SIMS to be a method for studying sorption depth profiles of MOFs.

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  • 167.
    Amorim, Rodrigo G.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory. Univ Fed Fluminense, Dept Fis, ICEx, Volta Redonda, RJ, Brazil..
    Rocha, Alexandre R.
    Univ Estadual Paulista, UNESP, Inst Fis Teor, Sao Paulo, Brazil..
    Scheicher, Ralph H.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Boosting DNA Recognition Sensitivity of Graphene Nanogaps through Nitrogen Edge Functionalization2016In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 120, no 34, p. 19384-19388Article in journal (Refereed)
    Abstract [en]

    One of the challenges for next generation DNA sequencing is to have a robust, stable, and reproducible nanodevice. In this work, we propose how to improve the sensing of DNA nucleobase using functionalized graphene nanogap as a solid state device. Two types of edge functionalization, namely, either hydrogen or nitrogen, were considered. We showed that, independent of species involved in the edge passivation, the highest-to-lowest order of the nucleobase transmissions is not altered, but the intensity is affected by several orders of magnitude. Our results show that nitrogen edge tends to p-dope graphene, and most importantly, it contributes with resonance states close to the Fermi level, which can be associated with the increased conductance. Finally, the translocation process of nucleobases passing through the nanogap was also investigated by varying their position from a certain height (from +3 to -3 angstrom) with respect to the graphene sheet to show that nitrogen-terminated sheets have enhanced sensitivity, as moving the nucleobase by approximately 1 angstrom reduces the conductance by up to 3 orders of magnitude.

  • 168.
    Amruth, C.
    et al.
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Luszczynska, Beata
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Szymanski, Marek Zdzislaw
    Örebro University, School of Science and Technology. Department of Engineering and Chemical Sciences, Karlstad University, Karlstad, Sweden.
    Ulanski, Jacek
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Albrecht, Ken
    Laboratory for Chemistry and Life Science, Tokyo Institute of Technology, Yokohama, Japan; JST-ERATO Yamamoto Atom Hybrid Project, Tokyo Institute of Technology, Yokohama, Japan; Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka, Japan.
    Yamamoto, Kimihisa
    Laboratory for Chemistry and Life Science, Tokyo Institute of Technology, Yokohama, Japan; Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka, Japan.
    Inkjet printing of thermally activated delayed fluorescence (TADF) dendrimer for OLEDs applications2019In: Organic electronics, ISSN 1566-1199, E-ISSN 1878-5530, Vol. 74, p. 218-227Article in journal (Refereed)
    Abstract [en]

    This study presents the inkjet printing of a novel OLED device with fully solution-processed organic layers that employ TADF material as an emitting layer. The ink was formulated using new TADF material, triazine core carbazole dendrimers with tert-butyl group at the periphery (tBuG2TAZ), dissolved in a mixture of two non-chlorinated solvents. The influence of the print resolution and the substrate temperature on morphology of the printed films was studied and optimized in ambient conditions. The optimized TADF dendrimer layer was then incorporated in the OLEDs as the emitting layer. The best-printed OLEDs exhibited a maximum current efficiency of 18 cd/A and maximum luminance of 6900 cd/m(2). Such values are comparable to the values obtained in spin coated devices made of the same TADF dendrimer. Further, the mobility of charge carriers extracted from transient electroluminescence measurements of printed OLEDs, when compared to reference OLEDs made by spin coating technique, showed similar values. Finally, we have demonstrated the possibility of patterning of emission the area of complex shapes merely by selectively printing the emission layer. These results demonstrate the potential application of the new dendrimer TADF emitters for the fabrication of efficient OLEDs by an inkjet printing technique.

  • 169.
    Amruth, C.
    et al.
    Lodz University of Technology, Poland.
    Szymanski, Marek Zdzislaw
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013). Örebro University.
    Luszczynska, Beata
    Lodz University of Technology, Poland.
    Ulanski, Jacek
    Lodz University of Technology, Poland.
    Inkjet printing of super yellow: Ink formulation, film optimization, OLEDs fabrication, and transient electroluminescence2019In: Scientific Reports, E-ISSN 2045-2322, Vol. 9, p. 1-10, article id 8493Article in journal (Refereed)
    Abstract [en]

    Inkjet printing technique allows manufacturing low cost organic light emitting diodes (OLEDs) in ambient conditions. The above approach enables upscaling of the OLEDs fabrication process which, as a result, would become faster than conventionally used vacuum based processing techniques. In this work, we use the inkjet printing technique to investigate the formation of thin active layers of well-known light emitting polymer material: Super Yellow (poly(para-phenylene vinylene) copolymer). We develop the formulation of Super Yellow ink, containing non-chlorinated solvents and allowing stable jetting. Optimization of ink composition and printing resolution were performed, until good quality films suitable for OLEDs were obtained. Fabricated OLEDs have shown a remarkable characteristics of performance, similar to the OLEDs fabricated by means of spin coating technique. We checked that, the values of mobility of the charge carriers in the printed films, measured by transient electroluminescence, are similar to the values of mobility measured in spin coated films. Our contribution provides a complete framework for inkjet printing of high quality Super Yellow films for OLEDs. The description of this method can be used to obtain efficient printed OLEDs both in academic and in industrial settings.

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  • 170.
    Amruth, C
    et al.
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Szymański, Marek
    Örebro University, School of Science and Technology. Department of Engineering and Chemical Sciences, Karlstad University, Karlstad, Sweden.
    Łuszczyńska, Beata
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Ulański, Jacek
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Inkjet Printing of Super Yellow: Ink Formulation, Film Optimization, OLEDs Fabrication, and Transient Electroluminescence2019In: Scientific Reports, E-ISSN 2045-2322, Vol. 9, no 1, article id 8493Article in journal (Refereed)
    Abstract [en]

    Inkjet printing technique allows manufacturing low cost organic light emitting diodes (OLEDs) in ambient conditions. The above approach enables upscaling of the OLEDs fabrication process which, as a result, would become faster than conventionally used vacuum based processing techniques. In this work, we use the inkjet printing technique to investigate the formation of thin active layers of well-known light emitting polymer material: Super Yellow (poly(para-phenylene vinylene) copolymer). We develop the formulation of Super Yellow ink, containing non-chlorinated solvents and allowing stable jetting. Optimization of ink composition and printing resolution were performed, until good quality films suitable for OLEDs were obtained. Fabricated OLEDs have shown a remarkable characteristics of performance, similar to the OLEDs fabricated by means of spin coating technique. We checked that, the values of mobility of the charge carriers in the printed films, measured by transient electroluminescence, are similar to the values of mobility measured in spin coated films. Our contribution provides a complete framework for inkjet printing of high quality Super Yellow films for OLEDs. The description of this method can be used to obtain efficient printed OLEDs both in academic and in industrial settings.

  • 171.
    An, Dong
    et al.
    Shenzhen Univ, Hlth Sci Ctr, Shenzhen Engn Lab Phosphorene & Optoelect,Affilia, Inst Translat Med,Dept Otolaryngol,Shenzhen Secon, Shenzhen 518060, Peoples R China.;Shenzhen Univ, Int Collaborat Lab 2D Mat Optoelect Sci & Technol, Minist Educ, Coll Optoelect Engn, Shenzhen 518060, Peoples R China..
    Fu, Jianye
    Shenzhen Univ, Hlth Sci Ctr, Shenzhen Engn Lab Phosphorene & Optoelect,Affilia, Inst Translat Med,Dept Otolaryngol,Shenzhen Secon, Shenzhen 518060, Peoples R China.;Shenzhen Univ, Int Collaborat Lab 2D Mat Optoelect Sci & Technol, Minist Educ, Coll Optoelect Engn, Shenzhen 518060, Peoples R China..
    Zhang, Bin
    Shenzhen Univ, Hlth Sci Ctr, Shenzhen Engn Lab Phosphorene & Optoelect,Affilia, Inst Translat Med,Dept Otolaryngol,Shenzhen Secon, Shenzhen 518060, Peoples R China.;Shenzhen Univ, Int Collaborat Lab 2D Mat Optoelect Sci & Technol, Minist Educ, Coll Optoelect Engn, Shenzhen 518060, Peoples R China..
    Xie, Ni
    Shenzhen Univ, Hlth Sci Ctr, Shenzhen Engn Lab Phosphorene & Optoelect,Affilia, Inst Translat Med,Dept Otolaryngol,Shenzhen Secon, Shenzhen 518060, Peoples R China.;Shenzhen Univ, Int Collaborat Lab 2D Mat Optoelect Sci & Technol, Minist Educ, Coll Optoelect Engn, Shenzhen 518060, Peoples R China..
    Nie, Guohui
    Shenzhen Univ, Hlth Sci Ctr, Shenzhen Engn Lab Phosphorene & Optoelect,Affilia, Inst Translat Med,Dept Otolaryngol,Shenzhen Secon, Shenzhen 518060, Peoples R China.;Shenzhen Univ, Int Collaborat Lab 2D Mat Optoelect Sci & Technol, Minist Educ, Coll Optoelect Engn, Shenzhen 518060, Peoples R China..
    Ågren, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Qiu, Meng
    Ocean Univ China, Minist Educ, Key Lab Marine Chem Theory & Technol, Qingdao 266100, Peoples R China..
    Zhang, Han
    Shenzhen Univ, Hlth Sci Ctr, Shenzhen Engn Lab Phosphorene & Optoelect,Affilia, Inst Translat Med,Dept Otolaryngol,Shenzhen Secon, Shenzhen 518060, Peoples R China.;Shenzhen Univ, Int Collaborat Lab 2D Mat Optoelect Sci & Technol, Minist Educ, Coll Optoelect Engn, Shenzhen 518060, Peoples R China..
    NIR-II Responsive Inorganic 2D Nanomaterials for Cancer Photothermal Therapy: Recent Advances and Future Challenges2021In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 31, no 32, article id 2101625Article, review/survey (Refereed)
    Abstract [en]

    Non-invasive cancer photothermal therapy (PTT) is a promising replacement for traditional cancer treatments. The second near-infrared region induced PTT (NIR-II PTT, 1000-1500 nm) with less energy dissipation has been developed for deeper-seated tumor treatment in recent years compared with the traditional first near-infrared light (750-1000 nm). In addition, the use of emerging inorganic 2D nanomaterials as photothermal agents (PTAs) further enhanced PTT efficiency due to their intrinsic photothermal properties. NIR-II light stimulated inorganic 2D nanomaterials for PTT is becoming a hot topic in both academic and clinical fields. This review summarizes the categories, structures, and photothermal conversion properties of inorganic 2D nanomaterials for the first time. The recent synergistic strategies of NIR-II responsive PTT combined with other treatment approaches including chemotherapy, chemodynamic therapy, photodynamic therapy, radiotherapy are summarized. The future challenges and perspectives on these 2D nanomaterials for NIR-II responsive PTT systems construction are further discussed.

  • 172. An, J.
    et al.
    Yang, X.
    Wang, W.
    Li, J.
    Wang, H.
    Yu, Z.
    Gong, C.
    Wang, X.
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. KTH, School of Information and Communication Technology (ICT), Centres, Zhejiang-KTH Joint Research Center of Photonics, JORCEP.
    Stable and efficient PbS colloidal quantum dot solar cells incorporating low-temperature processed carbon paste counter electrodes2017In: Solar Energy, ISSN 0038-092X, E-ISSN 1471-1257, Vol. 158, p. 28-33Article in journal (Refereed)
    Abstract [en]

    Colloidal quantum dot (CQD) solar cells with a ZnO/PbS-TBAI/PbS-EDT/carbon structure were prepared using a solution processing technique. A commercially available carbon paste that was processed at low-temperatures was used as a counter electrode in place of expensive noble metals, such as Au or Ag, which are used in traditional PbS CQD solar cells. These CQD solar cells exhibited remarkable photovoltaic performance with a short circuit density (Jsc) of 25.6 mA/cm2, an open circuit voltage (Voc) of 0.45 V, a fill factor (FF) of 51.8% and a power conversion efficiency (PCE) as high as 5.9%. A reference device with an Au counter electrode had a PCE of 6.0%. The PCE of the carbon-containing CQD solar cell remained stable for 180 days when tested in ambient atmosphere, while the PCE of the Au-containing CQD solar cell lost 48.3% of its original value. Electrochemical impedance spectroscopy (EIS) demonstrated that holes within the PbS CQD were effectively transported to the carbon counter electrode.

  • 173.
    An, Rong
    et al.
    Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
    Laaksonen, Aatto
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-10691 Stockholm, Sweden; Center of Advanced Research in Bionanoconjugates and Biopolymers, “Petru Poni” Institute of Macromolecular Chemistry, Iasi 700469, Romania; State Key Laboratory of Materials-Oriented and Chemical Engineering, Nanjing Tech University, Nanjing 211816, China.
    Wu, Muqiu
    Herbert Gleiter Institute of Nanoscience, School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
    Zhu, Yudan
    State Key Laboratory of Materials-Oriented and Chemical Engineering, Nanjing Tech University, Nanjing 211816, China.
    Shah, Faiz Ullah
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Lu, Xiaohua
    State Key Laboratory of Materials-Oriented and Chemical Engineering, Nanjing Tech University, Nanjing 211816, China.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Atomic force microscopy probing interactions and microstructures of ionic liquids at solid surfaces2022In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, no 14, p. 11098-11128Article, review/survey (Refereed)
    Abstract [en]

    Ionic liquids (ILs) are room temperature molten salts that possess preeminent physicochemical properties and have shown great potential in many applications. However, the use of ILs in surface-dependent processes, e.g. energy storage, is hindered by the lack of a systematic understanding of the IL interfacial microstructure. ILs on the solid surface display rich ordering, arising from coulombic, van der Waals, solvophobic interactions, etc., all giving near-surface ILs distinct microstructures. Therefore, it is highly important to clarify the interactions of ILs with solid surfaces at the nanoscale to understand the microstructure and mechanism, providing quantitative structure–property relationships. Atomic force microscopy (AFM) opens a surface-sensitive way to probe the interaction force of ILs with solid surfaces in the layers from sub-nanometers to micrometers. Herein, this review showcases the recent progress of AFM in probing interactions and microstructures of ILs at solid interfaces, and the influence of IL characteristics, surface properties and external stimuli is thereafter discussed. Finally, a summary and perspectives are established, in which, the necessities of the quantification of IL–solid interactions at the molecular level, the development of in situ techniques closely coupled with AFM for probing IL–solid interfaces, and the combination of experiments and simulations are argued.

  • 174.
    Anandhakumari, Govindharaj
    et al.
    Department of Physics, Gobi Arts & Science College, Gobichettipalayam, Erode, Tamilnadu-638 453, India.
    Jayabal, Palanisamy
    Department of Physics, Gobi Arts & Science College, Gobichettipalayam, Erode, Tamilnadu-638 453, India.
    Balasankar, Athinarayanan
    Department of Physics, Gobi Arts & Science College, Gobichettipalayam, Erode, Tamilnadu-638 453, India.
    Ramasundaram, Subramaniyan
    School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Korea.
    Oh, Tae Hwan
    School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Korea.
    Aruchamy, Kanakaraj
    School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Korea.
    Kallem, Parashuram
    Department of Environmental and Public Health, College of Health Sciences, Abu Dhabi University, Abu Dhabi, P.O. Box 59911, United Arab Emirates.
    Polisetti, Veerababu
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Synthesis of strontium oxide-zinc oxide nanocomposites by Co-precipitation method and its application for degradation of malachite green dye under direct sunlight2023In: Heliyon, E-ISSN 2405-8440, Vol. 9, no 10, article id e20824Article in journal (Refereed)
    Abstract [en]

    Photocatalysts workable under direct sunlight are the safe and cost-effective option for water purification. The nanocomposites of strontium oxide and zinc oxide (SZ NCs) were synthesized using coprecipitation method. The respective precursors of SZ NCs were subjected to alkaline hydrolysis and subsequently thermally treated to yield SZ NCs. The SZ NCs with different ZnO composition was synthesized by varying the concentration of ZnO precursor from 0.2 to 1 M. The structural properties of SZ NCs evaluated using X-Ray diffraction (XRD), Thermogravimetric analysis (TGA), and Differential thermal analysis DTA). The optical properties of SZ NCs studied using ultraviolet–visible (UV–Vis) spectroscopic study. The trend observed in the intensity of XRD peaks indicated the occurrence of Zn doping in the crystalline lattice of SrO and the formation of SrO–ZnO composite. Upon incorporation of 1 M of ZnO precursor, the grain size of the SrO was decreased from 49.3 to 27.6 nm. The weight loss in the thermal analysis indicates the removal of carbonates from the sample upon heating and shows the formation of an oxide structure. UV–Vis spectra confirmed that the presence of SrO enhanced the sunlight absorption of SZ NCs. The increase in the composition of ZnO precursors increased the bandgap of SrO (2.09 eV) to the level of ZnO (3.14 eV). SZ NCs exhibited heterostructure morphology, where the nanosized domains with varying shapes (layered and rod-like) were observed. Under direct sunlight conditions, SZ NCs prepared using 1 M/0.6 M of SrO/ZnO precursors exhibited 15–20 % higher photocatalytic efficiency than neat SrO and ZnO. In precise, 1 mg of this SZ NC was degraded 98 % of malachite green dye dissolved in water (10 ppm) under direct sunlight. Additionally, the thermal stability results showed that 18 % decomposition was obtained due to the degradation impurities in SrO/ZnO catalysts and the XRD results revealed that no structural change is obtained in SrO/ZnO photocatalysts after stability test. The SZ NCs can be effectively used as safe and economic sunlight photocatalysts for water purification in remote areas without the electricity.

  • 175.
    Anaraki, Elham Halvani
    et al.
    Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photomol Sci, CH-1015 Lausanne, Switzerland;Isfahan Univ Technol, Dept Mat Engn, Esfahan 8415683111, Iran.
    Kermanpur, Ahmad
    Isfahan Univ Technol, Dept Mat Engn, Esfahan 8415683111, Iran.
    Mayer, Matthew T.
    Ecole Polytech Fed Lausanne, Lab Photon & Interfaces, Inst Chem Sci & Engn, CH-1015 Lausanne, Switzerland;Helmholtz Zentrum Berlin, Young Investigator Grp Electrochem Convers CO2, Hahn Meitner Pl 1, D-14109 Berlin, Germany.
    Steier, Ludmilla
    Ecole Polytech Fed Lausanne, Lab Photon & Interfaces, Inst Chem Sci & Engn, CH-1015 Lausanne, Switzerland;Imperial Coll London, Dept Chem, London SW7 2AZ, England.
    Ahmed, Taha
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Turren-Cruz, Silver-Hamill
    Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photomol Sci, CH-1015 Lausanne, Switzerland.
    Seo, Jiyoun
    Ecole Polytech Fed Lausanne, Lab Photon & Interfaces, Inst Chem Sci & Engn, CH-1015 Lausanne, Switzerland.
    Luo, Jingshan
    Ecole Polytech Fed Lausanne, Lab Photon & Interfaces, Inst Chem Sci & Engn, CH-1015 Lausanne, Switzerland.
    Zakeeruddin, Shaik Mohammad
    Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photomol Sci, CH-1015 Lausanne, Switzerland;Ecole Polytech Fed Lausanne, Lab Photon & Interfaces, Inst Chem Sci & Engn, CH-1015 Lausanne, Switzerland.
    Tress, Wolfgang Richard
    Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photomol Sci, CH-1015 Lausanne, Switzerland;Ecole Polytech Fed Lausanne, Lab Photon & Interfaces, Inst Chem Sci & Engn, CH-1015 Lausanne, Switzerland.
    Edvinsson, Tomas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Graetzel, Michael
    Ecole Polytech Fed Lausanne, Lab Photon & Interfaces, Inst Chem Sci & Engn, CH-1015 Lausanne, Switzerland.
    Hagfeldt, Anders
    Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photomol Sci, CH-1015 Lausanne, Switzerland.
    Correa-Baena, Juan-Pablo
    Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photomol Sci, CH-1015 Lausanne, Switzerland;MIT, Dept Mech Engn, 77 Massachusetts Ave, Cambridge, MA 02139 USA.
    Low-Temperature Nb-Doped SnO2 Electron-Selective Contact Yields over 20% Efficiency in Planar Perovskite Solar Cells2018In: ACS Energy Letters, E-ISSN 2380-8195, Vol. 3, no 4, p. 773-778Article in journal (Refereed)
    Abstract [en]

    Low-temperature planar organic inorganic lead halide perovskite solar cells have been at the center of attraction as power conversion efficiencies go beyond 20%. Here, we investigate Nb doping of SnO2 deposited by a low-cost, scalable chemical bath deposition (CBD) method. We study the effects of doping on compositional, structural, morphological, and device performance when these layers are employed as electron-selective layers (ESLs) in planar-structured PSCs. We use doping concentrations of 0, 1, 5, and 10 mol % Nb to Sn in solution. The ESLs were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, atomic force microscopy, and ultraviolet visible spectroscopy. ESLs with an optimum 5 mol % Nb doping yielded, on average, an improvement of all the device photovoltaic parameters with a champion power conversion efficiency of 20.5% (20.1% stabilized).

  • 176.
    Andersson, Anton
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Brander, Linus
    Division of Built Environment—Infrastructure and Concrete, Research Institute of Sweden, SE-501 15 Borås, Sweden.
    Lennartsson, Andreas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Roos, Ake
    Boliden AB, SE-101 20 Stockholm, Sweden.
    Engström, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    A Method for Synthesizing Iron Silicate Slags to Evaluate Their Performance as Supplementary Cementitious Materials2023In: Applied Sciences, E-ISSN 2076-3417, Vol. 13, no 14, article id 8357Article in journal (Refereed)
    Abstract [en]

    Utilizing iron silicate copper slag as supplementary cementitious material (SCM) is a means to improve resource efficiency and lower the carbon dioxide emissions from cement production. Despite multiple studies on the performance of these slags in SCM applications, the variations in cooling procedure, grinding, and methods for evaluating reactivity limit the ability to assess the influence of chemical composition on reactivity from the literature data. In this study, a methodology was developed to synthesize iron silicate slags, which were then evaluated for their inherent reactivity using the R-3 calorimeter-based experiments. The results demonstrated that laboratory-scale granulation produced the same reactivity as industrially granulated slag. Furthermore, a synthesized triplicate sample showed high repeatability. Based on these two aspects, this method can be used to systematically study the influence of chemical composition on the inherent reactivity of iron silicate slags while producing results that are directly translatable to industrial slags.

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  • 177.
    Andersson, Anton
    et al.
    Luleå University of Technology, Sweden.
    Brander, Linus
    RISE Research Institutes of Sweden, Materials and Production, Product Realisation Methodology.
    Lennartsson, Andreas
    Luleå University of Technology, Sweden.
    Roos, Åke
    Boliden AB, Sweden.
    Engström, Fredrik
    Luleå University of Technology, Sweden.
    A Method for Synthesizing Iron Silicate Slags to Evaluate Their Performance as Supplementary Cementitious Materials2023In: Applied Sciences, E-ISSN 2076-3417, Vol. 13, no 14, article id 8357Article in journal (Refereed)
    Abstract [en]

    Utilizing iron silicate copper slag as supplementary cementitious material (SCM) is a means to improve resource efficiency and lower the carbon dioxide emissions from cement production. Despite multiple studies on the performance of these slags in SCM applications, the variations in cooling procedure, grinding, and methods for evaluating reactivity limit the ability to assess the influence of chemical composition on reactivity from the literature data. In this study, a methodology was developed to synthesize iron silicate slags, which were then evaluated for their inherent reactivity using the R3 calorimeter-based experiments. The results demonstrated that laboratory-scale granulation produced the same reactivity as industrially granulated slag. Furthermore, a synthesized triplicate sample showed high repeatability. Based on these two aspects, this method can be used to systematically study the influence of chemical composition on the inherent reactivity of iron silicate slags while producing results that are directly translatable to industrial slags. © 2023 by the authors.

  • 178.
    Andersson, Edvin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Solid State Physics.
    Spectroelectrochemical analysis of the Li-ion battery solid electrolyte interphase using simulated Raman spectra2020Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Lithium Ion Batteries (LIBs) are important in today's society, powering cars and mobile devices. LIBs consist of a negative anode commonly made of graphite, and a positive cathode commonly made from transition metal oxides. Between these electrodes are separators and organic solvent based electrolyte. Due to the high potential of LIBs the electrolyte is reduced at the anode. The electrolyte reduction results in the formation of a layer called the Solid Electrolyte Interphase (SEI), which prohibits the further breakdown of the electrolyte. Despite being researched for over50 years, the composition formation of the SEI is still poorly understood. The aim of this project is to develop strategies for efficient identification and classification of various active and intermediate components in the SEI, to, in turn, gain an understanding of the reactions taking place, which will help find routes to stabilize and tailor the composition of the SEI layer for long-term stability and optimal battery performance. For a model gold/li-ion battery electrolyte system, Raman spectra will be obtained using Surface Enhanced Raman Spectroscopy (SERS) in a spectroelectrochemical application where the voltage of the working gold electrode is swept from high to low potentials. Spectra of common components of the SEI as well as similar compounds will be simulated using Density Functional Theory (DFT). The DFT data is also used to calculate the spontaneity of reactions speculated to form the SEI. The simulated data will be validated by comparing it to experimental spectra from pure substances. The spectroelectrochemical SERS results show a clear formation of Li-carbonate at the SERS substrate, as well as the decomposition of the electrolyte into other species, according to the simulated data. It is however shown that there are several issues when modelling spectra, that makes it harder to correlate the simulated spectra with the spectroelectrochemical spectra. These issues include limited knowledge of the structure of the compounds thought to form on the anode surface, and incorrect choices in simulational parameters. To solve these issues, more work is needed in these areas, and the spectroelectrochemical methods used in this thesis needs to be combined with other experimental methods to narrow down the amount of compounds to be modelled. More work is also needed to avoid impurities in the electrolyte. Impurities leads to a thick inorganic layer which prohibits the observation of species in the organic layer.

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  • 179.
    Andersson, Edvin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Sångeland, Christofer
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Berggren, Elin
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Condensed Matter Physics of Energy Materials.
    Johansson, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Kühn, Danilo
    Lindblad, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Condensed Matter Physics of Energy Materials.
    Mindemark, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Hahlin, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Early-Stage Decomposition of Solid Polymer Electrolytes in Li-Metal Batteries2021In: Journal of Materials Chemistry, ISSN 0959-9428, E-ISSN 1364-5501, Vol. 9, no 39Article in journal (Refereed)
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  • 180.
    Andersson Ersman, Peter
    et al.
    RISE Research Institutes of Sweden, Digital Systems, Smart Hardware.
    Boda, Ulrika
    RISE Research Institutes of Sweden, Digital Systems, Smart Hardware.
    Petsagkourakis, Ioannis
    RISE Research Institutes of Sweden, Digital Systems, Smart Hardware.
    Åhlin, Jessica
    RISE Research Institutes of Sweden, Digital Systems, Smart Hardware.
    Posset, Uwe
    Fraunhofer, Germany.
    Schott, Marco
    Fraunhofer, Germany.
    Brooke, Robert
    RISE Research Institutes of Sweden, Digital Systems, Smart Hardware.
    Reflective and Complementary Transmissive All-Printed Electrochromic Displays Based on Prussian Blue2023In: Advanced Engineering Materials, ISSN 1438-1656, E-ISSN 1527-2648, Vol. 25, no 6, article id 2201299Article in journal (Refereed)
    Abstract [en]

    By combining the electrochromic (EC) properties of Prussian blue (PB) and poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), complementary EC displays manufactured by slot-die coating and screen printing on flexible plastic substrates are reported. Various display designs have been realized, resulting in displays operating in either transmissive or reflective mode. For the transmission mode displays, the color contrast is enhanced by the complementary switching of the two EC electrodes PB and PEDOT:PSS. Both electrodes are either exhibiting a concurrent colorless or blue appearance. For the displays operating in reflection mode, a white opaque electrolyte is used in conjunction with the EC properties of PB, resulting in a display device switching between a fully white state and a blue-colored state. The developments of the different device architectures, that either operate in reflection or transmission mode, demonstrate a scalable manufacturing approach of all-printed EC displays that may be used in a large variety of Internet of Things applications. © 2022 The Authors. 

  • 181.
    Andersson Ersman, Peter
    et al.
    RISE Acreo, Sweden.
    Lassnig, Roman
    RISE Acreo, Sweden.
    Strandberg, Jan
    RISE Acreo, Sweden.
    Tu, Deyu
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Keshmiri, Vahid
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Forchheimer, Robert
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Fabiano, Simone
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Gustafsson, Goran
    RISE Acreo, Sweden.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    All-printed large-scale integrated circuits based on organic electrochemical transistors2019In: Nature Communications, E-ISSN 2041-1723, Vol. 10, article id 5053Article in journal (Refereed)
    Abstract [en]

    The communication outposts of the emerging Internet of Things are embodied by ordinary items, which desirably include all-printed flexible sensors, actuators, displays and akin organic electronic interface devices in combination with silicon-based digital signal processing and communication technologies. However, hybrid integration of smart electronic labels is partly hampered due to a lack of technology that (de)multiplex signals between silicon chips and printed electronic devices. Here, we report all-printed 4-to-7 decoders and seven-bit shift registers, including over 100 organic electrochemical transistors each, thus minimizing the number of terminals required to drive monolithically integrated all-printed electrochromic displays. These relatively advanced circuits are enabled by a reduction of the transistor footprint, an effort which includes several further developments of materials and screen printing processes. Our findings demonstrate that digital circuits based on organic electrochemical transistors (OECTs) provide a unique bridge between all-printed organic electronics (OEs) and low-cost silicon chip technology for Internet of Things applications.

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  • 182.
    Andersson, Felicia
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry.
    A Quantum Chemical Investigation of Chemical Vapour Deposition of Fe using Ferrocene and Plasma Electrons2023Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Thin films provide a remarkable asset, as depositing a thin surface layer can completely alter a material’s characteristics and provide new, inexpensive, and valuable properties. In 2020, a new Chemical Vapour Deposition (CVD) approach was developed at Linköping University, using plasma electrons as reducing agents for the deposition of metallic thin films. To understand the CVD approach, comprehension of the deposition chemistry is crucial. In this thesis, I have performed a theoretical examination of the gas phase and surface chemistry of ferrocene in the recently developed CVD method to form metallic iron thin films, using plasma electrons as reducing agents. Results show that ferrocene anion formation and dissociation are probable in the gas phase, depending on the energy of the plasma electrons. It gets successively easier to dissociate the complex after gaining electrons. The most probable gas phase species leading to film formation was determined as FeCp2-, FeCp, and Cp− under the normal deposition parameters. An electron energy above 220 kJ/mol would suffice for ion formation and dissociation to form FeCp and Cp− fragments. On the surface, ferrocene’s vertical and horizontal adsorption is equally probable, with energies around -72 kJ/mol. Cp, Fe, and FeCp with Fe facing towards the surface interacts stronger with the surface than ferrocene, with adsorption energies of -179, -279 kJ/mol, and -284 kJ/mol. FeCp with Fe facing up from the surface had adsorption energy of -23 kJ/mol. As the surface bonding of Fe and FeCp with Fe facing the surface is stronger than for the other species, this poses a possible way of tuning the CVD method to limit carbon impurities. By providing above 180 kJ/mol energy, for example in the form of heating the substrate, the unwanted species FeCp2, Cp, and FeCp with the ring facing downwards would desorb from the surface, leaving the Fe and FeCp fragments with iron facing towards the surface still adsorbed. This poses a possible way of reducing carbon impurities.

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    A Quantum Chemical Investigation of Chemical Vapour Deposition of Fe using Ferrocene and Plasma Electrons
  • 183.
    Andersson, Håkan S.
    et al.
    University of Kalmar, School of Pure and Applied Natural Sciences. Cranfield University, UK.
    Piletsky, Sergey A
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Mosbach, Klaus
    Lund University.
    Nicholls, Ian A.
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Koch-Schmidt, Ann-Christin
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Cooperative Binding in Molecularly Imprinted Polymers against (-)-Nicotine.1997Conference paper (Other academic)
  • 184.
    Andersson, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Synthesis of polycarbonate polymer electrolytes for lithium ion batteries and study of additives to raise the ionic conductivity2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Polymer electrolyte films based on poly(trimethylene carbonate) (PTMC) mixed with LiTFSI salt in different compositions were synthesized and investigated as electrolytes for lithium ion batteries, where the ionic conductivity is the most interesting material property. Electrochemical impedance spectroscopy (EIS) and DSC were used to measure the ionic conductivity and thermal properties, respectively. Additionally, FTIR and Raman spectroscopy were used to examine ion coordination in the material. Additives of nanosized TiO2 and powders of superionically conducting Li1.3Al0.3Ti1.7(PO4)3 were investigated as enhancers of ionic conductivity, but no positive effect could be shown. The most conductive composition was found at a [Li+]:[carbonate] ratio of 1, corresponding to a salt concentration of 74 percent by weight, which showed an ionic conductivity of 2.0 × 10–6 S cm–1 at 25 °C and 2.2 × 10–5 S cm–1 at 60 °C, whereas for even larger salt concentrations, the mechanical durability of the polymeric material was dramatically reduced, preventing use as a solid electrolyte material. Macroscopic salt crystallization was also observed for these concentrations. Ion coordination to carbonyls on the polymer chain was examined for high salt content compositions with FTIR spectroscopy, where it was found to be relatively similar between the samples, possibly indicating saturation. Moveover, with FTIR, the ion-pairing was found to increase with salt concentration. The ionic conductivity was found to be markedly lower after 7 weeks of aging of the materials with highest salt concentrations.

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  • 185.
    Andersson, Linnéa
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Akhtar, Farid
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Ojuva, Arto
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Bergström, Lennart
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Colloidal processing and CO2-capture performance of hierarchically porous Al2O3-zeolite 13X composites2012In: Journal of Ceramic Science and Technology, ISSN 2190-9385, Vol. 3, no 1, p. 9-16Article in journal (Refereed)
    Abstract [en]

    Hierarchically porous composites for CO2-capture have been produced by coating the inner walls of foam-like macroporous alumina monoliths, produced by templated synthesis, with microporous zeolite 13X particles. Homogeneous and dense coatings of the particulate adsorbent were obtained when the impregnation process was performed at a pH above 9. At this pH-level the colloidally stable suspensions of the negatively charged zeolite 13X particles could fill all the voids of the highly connected pore space of the alumina supports and attach to the monolith walls, which had been pre-coated with poly(ethylene imine). A CO2-uptake as high as 5 mmol CO2/g zeolite 13X was achieved for alumina-zeolite 13X composites through minimisation of the added inorganic binder, kaolin, to only 3.0 wt% with respect to zeolite content, and through optimisation of the thermal treatment.

  • 186.
    Andersson, Rassmus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Hernández, Guiomar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    See, Jennifer
    Brewer Sci, Rolla, MO 65401 USA..
    Flaim, Tony D.
    Brewer Sci, Rolla, MO 65401 USA..
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Mindemark, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Designing Polyurethane Solid Polymer Electrolytes for High-Temperature Lithium Metal Batteries2022In: ACS Applied Energy Materials, E-ISSN 2574-0962, Vol. 5, no 1, p. 407-418Article in journal (Refereed)
    Abstract [en]

    Potentially high-performance lithium metal cells in extreme high-temperature electrochemical environments is a challenging but attractive battery concept that requires stable and robust electrolytes to avoid severely limiting lifetimes of the cells. Here, the properties of tailored polyester and polycarbonate diols as the soft segments in polyurethanes are investigated and electrochemically evaluated for use as solid polymer electrolytes in lithium metal batteries. The polyurethanes demonstrate high mechanical stability against deformation at low flow rates and moreover at temperatures up above 100 degrees C, enabled by the hard urethane segments. The results further indicate transferrable ion transport properties of the pure polymers when incorporated as the soft segments in the polyurethanes, offering designing opportunities of the polyurethane by tuning the soft segment ratio and composition. Long-term electrochemical cycling of polyurethane-containing cells in lithium metal batteries at 80 degrees C proves the stability at elevated temperatures as well as the compatibility with lithium metal with stable cycling maintained after 2000 cycles.

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  • 187.
    Andersson, Richard L.
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.
    Ström, Valter
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Engineering Material Physics.
    Gedde, Ulf W.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.
    Mallon, Peter E.
    Hedenqvist, Mikael S.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.
    Olsson, Richard T.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.
    Micromechanics of ultra-toughened electrospun PMMA/PEO fibres as revealed by in-situ tensile testing in an electron microscope2014In: Scientific Reports, E-ISSN 2045-2322, Vol. 4, p. 6335-Article in journal (Refereed)
    Abstract [en]

    A missing cornerstone in the development of tough micro/nano fibre systems is an understanding of the fibre failure mechanisms, which stems from the limitation in observing the fracture of objects with dimensions one hundredth of the width of a hair strand. Tensile testing in the electron microscope is herein adopted to reveal the fracture behaviour of a novel type of toughened electrospun poly(methyl methacrylate)/poly(ethylene oxide) fibre mats for biomedical applications. These fibres showed a toughness more than two orders of magnitude greater than that of pristine PMMA fibres. The in-situ microscopy revealed that the toughness were not only dependent on the initial molecular alignment after spinning, but also on the polymer formulation that could promote further molecular orientation during the formation of micro/nano-necking. The true fibre strength was greater than 150 MPa, which was considerably higher than that of the unmodified PMMA (17 MPa). This necking phenomenon was prohibited by high aspect ratio cellulose nanocrystal fillers in the ultra-tough fibres, leading to a decrease in toughness by more than one order of magnitude. The reported necking mechanism may have broad implications also within more traditional melt-spinning research.

  • 188.
    Andronic, L.
    et al.
    Transilvania University of Braso, Romania.
    Moldarev, D.
    Institute for Energy Technology, Norway.
    Deribew, Dargie
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Moons, Ellen
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Karazhanov, S. Z.
    Institute for Energy Technology, Norway.
    Photocatalytic self-cleaning properties of thin films of photochromic yttrium oxyhydride2022In: Journal of Solid State Chemistry, ISSN 0022-4596, E-ISSN 1095-726X, Vol. 316, article id 123599Article in journal (Refereed)
    Abstract [en]

    Oxyhydride of yttrium (YHO) belongs to an emerging class of materials, with oxide and hydride anions sharingthe same sites in the lattice. Under sunlight irradiation, the material is transparent to visible light with trans-parency exceeding 85% and can absorb about 10% of sunlight. Furthermore, increasing light transmittance in thevisible light enhanced the self-cleaning properties of the coated materials, making these materials promisingcandidates for smart windows applications. However, the light-absorbing properties of the materials wereincreased with exposure time, and in the photodarkening state, they can absorb about 40% of sunlight. Kelvinprobe measurements show work function values between 2.9 and 4.2 eV for YHO, depending on the H2/Arpressure in the deposition chamber. Using the Kelvin probe, we demonstrate that the work function decreaseswith decreasing deposition pressure and hydrogen flow. Measurements under solar light reveal a decrease of workfunction by 0.2 eV followed by a slow relaxation with the light off. Moreover, the self-cleaning test shows that theoxyhydroxide thin films have excellent photocatalytic activity and total self-cleaning in 40 h.

  • 189.
    Andruszkiewicz, Aneta
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Zhang, Xiaoliang
    Beihang Univ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China.
    Johansson, Malin B.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Yuan, Lin
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Johansson, Erik M. J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Perovskite and quantum dot tandem solar cells with interlayer modification for improved optical semitransparency and stability2021In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 13, no 12, p. 6234-6240Article in journal (Refereed)
    Abstract [en]

    In this work, four-terminal (4T) tandem solar cells were fabricated by using a methylammonium lead iodide (MAPbI3) perovskite solar cell (PSC) as the front-cell and a lead sulfide (PbS) colloidal quantum dot solar cell (CQDSC) as the back-cell. Different modifications of the tandem interlayer, at the interface between the sub-cells, were tested in order to improve the infrared transparency of the perovskite sub-cell and consequently increase the utilization of infrared (IR) light by the tandem system. This included the incorporation of a semi-transparent thin gold electrode (Au) on the MAPbI3 solar cell, followed by adding a molybdenum(VI) oxide (MoO3) layer or a surlyn layer. These interlayer modifications resulted in an increase of the IR transmittance to the back cell and improved the optical stability, compared to that in the reference devices. This investigation shows the importance of the interlayer, connecting the PSC with a strong absorption in the visible region and the CQDSC with a strong infrared absorption to obtain efficient next-generation tandem photovoltaics (PVs).

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  • 190.
    André, Magnus
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Malmström, Maria E.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Neretnieks, Ivars
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Determining sorption coefficients in intact rock using an electrical potential gradient as a driving force for migration2006In: Scientific Basis for Nuclear Waste Management XXIX / [ed] VanIseghem, P, WARRENDALE, PA: MATERIALS RESEARCH SOCIETY , 2006, Vol. 932, p. 975-982Conference paper (Refereed)
    Abstract [en]

    The transport of radionuclides in indigenous rock is greatly affected by the sorption of cations in the porous rock matrix. For the determination of sorption coefficients, batch experiments have traditionally been used. For these experiments, the rock sample is crushed into fine particles to reduce the experimental time. However, this procedure increases the specific surface area of the sample and the new surfaces created could have different sorption qualities than the naturally occurring surfaces, which may impair the results of sorption coefficient determinations. A new method for determining sorption coefficients in intact rock is being developed, using electromigration as a means to speed up the transport process, thereby allowing for faster equilibration between the rock sample and the tracer solution. Here, we report results from preliminary experiments, using cesium as a sorbing tracer, showing a consistent difference between sorption coefficients obtained using electromigration methods on intact rock samples and traditional batch experiments on crushed samples.

  • 191.
    Andrén, Daniel
    et al.
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Länk, Nils Odebo
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Sípová-Jungová, Hana
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Jones, Steven
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Johansson, Peter
    Örebro University, School of Science and Technology. Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Käll, Mikael
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Surface Interactions of Gold Nanoparticles Optically Trapped against an Interface2019In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 123, no 26, p. 16406-16414Article in journal (Refereed)
    Abstract [en]

    Particles that diffuse in close proximity to a surface are expected to behave differently than in free solution because the surface interaction will influence a number of physical properties, including the hydrodynamic, optical, and thermal characteristics of the particle. Understanding the influence of such effects is particularly important in view of the increasing interest in laser tweezing of colloidal resonant nanoparticles for applications such as nanomotors and optical printing and for investigations of unconventional optical forces. Therefore, we used total internal reflection microscopy to probe the interaction between a glass surface and individual similar to 100 nm gold nanoparticles trapped by laser tweezers. The results show that particles can be optically confined at controllable distances ranging between similar to 30 and similar to 90 nm from the surface, depending on the radiation pressure of the trapping laser and the ionic screening of the surrounding liquid. Moreover, the full particle-surface distance probability distribution can be obtained for single nanoparticles by analyzing temporal signal fluctuations. The experimental results are in excellent agreement with Brownian dynamics simulations that take the full force field and photothermal heating into account. At the observed particle-surface distances, translational friction coefficients increase by up to 60% compared to freely diffusing particles, whereas the rotational friction and thermal dissipation are much less affected. The methodology used here is general and can be adapted to a range of single nanoparticle-surface interaction investigations.

  • 192.
    Andrén, Oliver C. J.
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Zhang, Yuning
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Lundberg, Pontus
    Hawker, Craig J.
    Nyström, Andreas M.
    Malkoch, Michael
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Therapeutic Nanocarriers via Cholesterol Directed Self-Assembly of Well-Defined Linear-Dendritic Polymeric Amphiphiles2017In: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 29, no 9, p. 3891-3898Article in journal (Refereed)
    Abstract [en]

    A novel platform of fluorescently labeled nanocarriers (NCs) is herein proposed based on amphiphilic linear-dendritic polymeric hybrids. These sophisticated polymers were synthesized with a high degree of structural control at a macro-molecular level, displayed hydrophobic cholesterol compartments as chain-terminus groups of the dendritic block and hydrophilic bifunctional linear poly(ethylene glycol) (PEG) block. Spherical supramolecular assemblies with therapeutically relevant properties were successfully achieved including (i) sizes in the region of 100 to 200 nm; (ii) narrow dispersity profile with values close to 0.12; and (iii) self-assembly down to nanomolar concentrations. The modular nature of the NCs permitted the encapsulation of single or dual anticancer drugs and in parallel provide intracellular fluorescent traceability. As polymer therapeutics, the NCs were proven to penetrate the cancerous cell membranes and deliver the cargo of drugs into the nuclei as well as the cytoplasm and mitochondria. The dual drug delivery of both doxorubicin (DOX) and triptolide substantially enhanced the therapeutic efficacy with a 63% significant increase against resistant breast cancer cells when compared to free DOX.

  • 193. Anikina, E. V.
    et al.
    Banerjee, A.
    KTH Royal Inst Technol, Dept Mat & Engn, Appl Mat Phys, S-10044 Stockholm, Sweden..
    Beskachko, V. P.
    South Ural State Univ, Inst Nat Sci & Math, 76 Lenin Prospekt, Chelyabinsk 454014, Russia..
    Ahuja, Rajeev
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory. KTH Royal Inst Technol, Dept Mat & Engn, Appl Mat Phys, S-10044 Stockholm, Sweden..
    Influence of Kubas-type interaction of B-Ni codoped graphdiyne with hydrogen molecules on desorption temperature and storage efficiency2020In: Materials Today Energy, ISSN 2468-6069, Vol. 16, article id UNSP 100421Article in journal (Refereed)
    Abstract [en]

    We have investigated functionalized 2D carbon allotrope, graphdiyne (GDY), as a promising hydrogen storage media. Density functional theory with a range of vdW corrections was employed to study Ni decoration of pristine and boron-doped GDY and the interaction of resulting structures with molecular hydrogen. We showed that boron-doped GDY is thermally stable at 300 K, though, its synthesis requires an endothermic reaction. Also, boron doping enhances Ni binding with the graphdiyne by increasing the charge transfer from Ni to GDY. Ni doping drastically influenced hydrogen adsorption energies: they rise from similar to 70 meV per H-2 molecule on pristine GDY to a maximum of 1.29 eV per H-2 becoming too high in value for room temperature reversible applications. Boron doping improves the situations: in this case, after Ni decoration desorption temperature estimation is similar to 300-500 K. Overall, each Ni adatom on B-doped GDY can bind only one H-2 molecule within the needed energy range, which gives low hydrogen uptake (similar to 1.2 wt%). However, doping with boron led to the decrease in the value of hydrogen adsorption energy and good desorption temperature estimations, therefore, codoping of metal atoms and boron could be an effective strategy for other transition metals.

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  • 194.
    Anikina, Ekaterina
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory. South Ural State Univ, Inst Nat Sci & Math, 76 Lenin Prospekt, Chelyabinsk 454080, Russia..
    Banerjee, Amitava
    Royal Inst Technol KTH, Dept Mat & Engn, Appl Mat Phys, S-10044 Stockholm, Sweden..
    Beskachko, Valery
    South Ural State Univ, Inst Nat Sci & Math, 76 Lenin Prospekt, Chelyabinsk 454080, Russia..
    Ahuja, Rajeev
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory. Royal Inst Technol KTH, Dept Mat & Engn, Appl Mat Phys, S-10044 Stockholm, Sweden..
    Li-decorated carbyne for hydrogen storage: charge induced polarization and van't Hoff hydrogen desorption temperature2020In: Sustainable Energy & Fuels, E-ISSN 2398-4902, Vol. 4, no 2, p. 691-699Article in journal (Refereed)
    Abstract [en]

    We have studied carbyne as a promising hydrogen storage material. Density functional theory simulations with vdW corrections have been used to investigate lithium sorption on carbyne and the interaction of pristine and Li-functionalized carbon chains with molecular hydrogen. We showed that Li adatoms at small concentrations stay atomically dispersed on carbyne, donating 0.9e to the chain. Moreover, in the presence of Li, hydrogen adsorption energy increases by more than 5 times in comparison with pristine carbyne. Overall, up to three hydrogen molecules per Li adatom have an adsorption energy close to the range of 200-600 meV per H-2, which is necessary for effective sorption/desorption cycles. The resulting theoretical uptake (7.1 wt%) is higher than the U.S. Department of Energy's ultimate goal (6.5 wt%). The calculated van't Hoff desorption temperatures exceed considerably the boiling point of liquid nitrogen. Our results confirm the potential of Li-decorated carbyne for hydrogen storage.

  • 195.
    Anikina, Ekaterina
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory. South Ural State Univ, Inst Nat Sci & Math, 76 Lenin Prospekt, Chelyabinsk 454080, Russia.
    Banerjee, Amitava
    KTH Royal Inst Technol, Dept Mat & Engn, Appl Mat Phys, S-10044 Stockholm, Sweden.
    Beskachko, Valery
    South Ural State Univ, Inst Nat Sci & Math, 76 Lenin Prospekt, Chelyabinsk 454080, Russia.
    Ahuja, Rajeev
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory. KTH Royal Inst Technol, Dept Mat & Engn, Appl Mat Phys, S-10044 Stockholm, Sweden.
    Li-Functionalized Carbon Nanotubes for Hydrogen Storage: Importance of Size Effects2019In: ACS APPLIED NANO MATERIALS, ISSN 2574-0970, Vol. 2, no 5, p. 3021-3030Article in journal (Refereed)
    Abstract [en]

    We investigated Li-doped carbon nanotubes (CNTs) as a promising hydrogen storage media. In this computational model, we considered isolated lithium atom adsorbed on a CNT wall as an adsorption site for hydrogen. We focused on the influence of size effects on the structural and energetic characteristics of CNT(n,n)@Li+kH(2) complexes where n = 5, 7, 9; k = 1,..., 6; N, = 4, 5, 6 (N-c is translation length of CNT, expressed in terms of a number of CNT unit cells). We proved that modeled CNT length substantially influences internal sorption of Li and hydrogen on the narrow tube (5,5), which subsequently alters the adsorption energies of H-2 molecules and causes the deformation of the carbon framework. Moreover, the size effects are not pronounced in the case of external sorption for all considered CNT translation lengths and diameters. We have not observed any noticeable qualitative difference between internal and external hydrogen sorption in the nanotube wider than CNT(5,5). In the case of external adsorption on all considered nanotubes, doping with Li increases hydrogen adsorption energies of up to four H-2 molecules by 100 meV in comparison with pure CNTs. And the local density approximation estimations (similar to 250 meV/H-2) of adsorption energy on Li-decorated CNTs exceed the lowest requirement proposed by the U.S. Department of Energy (200 meV/H-2). In the case of internal sorption on Li-functionalized tubes, the generalized gradient approximation also gives hydrogen adsorption energies in the desired range of 200-600 meV/H-2. However, steric hindrances could prevent sufficient hydrogen uptakes (less than 2 wt % inside CNT(5,5)). We believe that our findings on the size effects are important for estimation of CNT's hydrogen storage properties.

  • 196.
    Anikina, Ekaterina
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory. South Ural State Univ, Inst Nat Sci & Math, 76 Lenin Prospekt, Chelyabinsk 454014, Russia..
    Hussain, Tanveer
    Univ Western Australia, Sch Mol Sci, Perth, WA 6009, Australia..
    Beskachko, Valery
    South Ural State Univ, Inst Nat Sci & Math, 76 Lenin Prospekt, Chelyabinsk 454014, Russia..
    Ahuja, Rajeev
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory. KTH Royal Inst Technol, Dept Mat & Engn, Appl Mat Phys, S-10044 Stockholm, Sweden..
    Elucidating hydrogen storage properties of two-dimensional siligraphene (SiC8) monolayers upon selected metal decoration2020In: Sustainable Energy & Fuels, E-ISSN 2398-4902, Vol. 4, no 11, p. 5578-5587Article in journal (Refereed)
    Abstract [en]

    Density functional theory calculations with dispersion corrections were employed to investigate the hydrogen (H-2) adsorptive properties of siligraphene (SiC8), pristine and decorated with selected alkali (Li, Na, and K) and alkaline-earth (Be, Mg, and Ca) metals. We found that all the considered metals (Me), except Mg and Be, bind strongly to SiC8 even at high doping concentrations (SiC8Me2) by donating a major portion of their valence electrons to SiC8. Ab initio molecular dynamics (AIMD) simulations confirmed the thermal stabilities of SiC8Me2 (Me = Li, Na, K, Ca) at 300 K. We showed that Li, Na, and Ca-doped SiC8 adsorbed multiple H-2 molecules with binding energies (E-bind) at least two times stronger than that of the pristine SiC8 (Epristinebind = -70 meV per H-2). Overall, both SiC8Li2 and SiC8Ca2 adsorbed two and four H-2 molecules per metal adatom, respectively, having E-bind within the desirable range for an effective adsorption/desorption process. The resulting gravimetric densities of SiC8Li2 and SiC8Ca2 were 5.5 wt% and 7.3 wt%, respectively, surpassing the U.S. Department of Energy's 2025 goal of 5.5 wt%. The estimated H-2 desorption temperatures exceed substantially the boiling point of liquid nitrogen, confirming the potential of light metal decorated SiC8 as a promising material for H-2 storage.

  • 197.
    Anikina, Ekaterina
    et al.
    South Ural State Univ, Inst Nat Sci & Math, Chelyabinsk 454014, Russia.;Uppsala Univ, Dept Phys & Astron, Mat Theory Div, S-75120 Uppsala, Sweden..
    Hussain, Tanveer
    Univ Western Australia, Sch Mol Sci, Perth, WA 6009, Australia..
    Beskachko, Valery
    South Ural State Univ, Inst Nat Sci & Math, Chelyabinsk 454014, Russia..
    Bae, Hyeonhu
    Konkuk Univ, Dept Phys, Seoul 05029, South Korea..
    Lee, Hoonkyung
    Konkuk Univ, Dept Phys, Seoul 05029, South Korea..
    Ahuja, Rajeev
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy. Uppsala UniKTH Royal Inst Technol, Appl Mat Phys, Dept Mat & Engn, S-10044 Stockholm, Sweden..
    Tunning Hydrogen Storage Properties of Carbon Ene-Yne Nanosheets through Selected Foreign Metal Functionalization2020In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 124, no 31, p. 16827-16837Article in journal (Refereed)
    Abstract [en]

    In this study, we have employed density functional theory with a range of van der Waals corrections to study geometries, electronic structures, and hydrogen (H-2) storage properties of carbon ene-yne (CEY) decorated with selected alkali (Na, K) and alkaline-earth metals (Mg, Ca). We found that all metals, except Mg, bind strongly by donating a major portion of their valence electrons to the CEY monolayers. Thermal stabilities of representative systems, Ca-decorated CEY monolayers, have been confirmed through ab initio molecular dynamics simulations (AIMD). We showed that each metal cation adsorbs multiple H-2 with binding energies (E-bind) considerably stronger than on pristine CEY. Among various metal dopants, Ca stands out with the adsorption of five H-2 per each Ca having E-bind values within the desirable range for effective adsorption/desorption process. The resulting gravimetric density for CEY@Ca has been found around 6.0 wt % (DFT-D3) and 8.0 wt % (LDA), surpassing the U.S. Department of Energy's 2025 goal of 5.5 wt %. The estimated H-2 desorption temperature in CEY@Ca exceeds substantially the boiling point of liquid nitrogen, which confirms its potential as a practical H-2 storage medium. We have also employed thermodynamic analysis to explore the H-2 adsorption/desorption mechanism at varied conditions of temperature and pressure for real-world applications.

  • 198.
    Anikina, Ekaterina
    et al.
    South Ural State Univ, Inst Nat Sci & Math, Chelyabinsk 454014, Russia.;Uppsala Univ, Dept Phys & Astron, Mat Theory Div, S-75120 Uppsala, Sweden..
    Hussain, Tanveer
    Univ Western Australia, Sch Mol Sci, Perth, WA 6009, Australia..
    Beskachko, Valery
    South Ural State Univ, Inst Nat Sci & Math, Chelyabinsk 454014, Russia..
    Bae, Hyeonhu
    Konkuk Univ, Dept Phys, Seoul 05029, South Korea..
    Lee, Hoonkyung
    Konkuk Univ, Dept Phys, Seoul 05029, South Korea..
    Ahuja, Rajeev
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Properties. Uppsala Univ, Dept Phys & Astron, Mat Theory Div, S-75120 Uppsala, Sweden.;KTH Royal Inst Technol, Appl Mat Phys, Dept Mat & Engn, S-10044 Stockholm, Sweden..
    Tunning Hydrogen Storage Properties of Carbon Ene-Yne Nanosheets through Selected Foreign Metal Functionalization2020In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 124, no 31, p. 16827-16837Article in journal (Refereed)
    Abstract [en]

    In this study, we have employed density functional theory with a range of van der Waals corrections to study geometries, electronic structures, and hydrogen (H-2) storage properties of carbon ene-yne (CEY) decorated with selected alkali (Na, K) and alkaline-earth metals (Mg, Ca). We found that all metals, except Mg, bind strongly by donating a major portion of their valence electrons to the CEY monolayers. Thermal stabilities of representative systems, Ca-decorated CEY monolayers, have been confirmed through ab initio molecular dynamics simulations (AIMD). We showed that each metal cation adsorbs multiple H-2 with binding energies (E-bind) considerably stronger than on pristine CEY. Among various metal dopants, Ca stands out with the adsorption of five H-2 per each Ca having E-bind values within the desirable range for effective adsorption/desorption process. The resulting gravimetric density for CEY@Ca has been found around 6.0 wt % (DFT-D3) and 8.0 wt % (LDA), surpassing the U.S. Department of Energy's 2025 goal of 5.5 wt %. The estimated H-2 desorption temperature in CEY@Ca exceeds substantially the boiling point of liquid nitrogen, which confirms its potential as a practical H-2 storage medium. We have also employed thermodynamic analysis to explore the H-2 adsorption/desorption mechanism at varied conditions of temperature and pressure for real-world applications.

  • 199.
    Anil Kumar, Puri
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Solid State Physics. Indian Assoc Cultivat Sci, Sch Mat Sci, Kolkata 700032, India..
    Nag, Abhishek
    Indian Assoc Cultivat Sci, Sch Mat Sci, Kolkata 700032, India..
    Mathieu, Roland
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Solid State Physics.
    Das, Ranjan
    Indian Inst Sci, Solid State & Struct Chem Unit, Bengaluru 560012, India..
    Ray, Sugata
    Indian Assoc Cultivat Sci, Sch Mat Sci, Kolkata 700032, India..
    Nordblad, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Solid State Physics.
    Hossain, Akmal
    Indian Inst Sci, Solid State & Struct Chem Unit, Bengaluru 560012, India..
    Cherian, Dona
    Indian Inst Sci, Solid State & Struct Chem Unit, Bengaluru 560012, India..
    Venero, Diego Alba
    ISIS Neutron & Muon Source, STFC Rutherford Appleton Lab, Didcot OX11 OQX, England..
    DeBeer-Schmitt, Lisa
    Oak Ridge Natl Lab, Large Scale Struct Grp, Neutron Sci Directorate, Oak Ridge, TN 37831 USA..
    Karis, Olof
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Sarma, D. D.
    Indian Inst Sci, Solid State & Struct Chem Unit, Bengaluru 560012, India..
    Magnetic polarons and spin-glass behavior in insulating La1-xSrxCoO3 (x = 0.125 and 0.15)2020In: Physical Review Research, E-ISSN 2643-1564, Vol. 2, no 4, article id 043344Article in journal (Refereed)
    Abstract [en]

    The evolution of magnetic polarons in Sr doped LaCoO3 (La1-xSrxCoO3) single crystal and polycrystalline samples are investigated by employing dc and ac magnetic measurement and small angle neutron scattering (SANS) techniques. The effect of magnetic field and temperature on magnetic polarons is experimentally studied for La0.875Sr0.125CoO3 and La0.85Sr0.15CoO3 compounds that belong to the spin glass insulating regime of the broader compositional phase diagram of this system. Langevin analyses of the isothermal magnetization curves in the notional paramagnetic regime prove the existence of magnetic polarons with large moments. The dc field superimposed ac susceptibility data and the analysis of the glassy dynamics prove that the size of polarons in 15% Sr doped crystal increase as the field is increased while the field effect is not visible in the 12.5% Sr doped crystal. A polycrystalline sample of La0.85Sr0.15CoO3 is analyzed by SANS experiments, which confirm nonzero correlation length at temperatures far above the macroscopic ordering temperature and hence the presence of magnetic polarons.

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  • 200.
    Anithaa, V. S.
    et al.
    Bharathiar Univ, Dept Phys, Coimbatore 641046, India..
    Suresh, Rahul
    Siberian Fed Univ, Int Res Ctr Spect & Quantum Chem IRC SQC, 79 Svobodny pr, Krasnoyarsk 660041, Russia..
    Kuklin, Artem V.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Vijayakumar, S.
    Bharathiar Univ, Dept Med Phys, Coimbatore 641046, India..
    Adsorption of volatile organic compounds on pristine and defected nanographene2022In: Computational and Theoretical Chemistry, ISSN 2210-271X, E-ISSN 2210-2728, Vol. 1211, article id 113664Article in journal (Refereed)
    Abstract [en]

    Adsorption of volatile organic compounds (VOCs) which are a class of air pollutants affecting the environment and human health is considered as the favourable technology for enrichment, separation and utilization of VOCs. In the present work, the adsorption properties of air polluting carbocyclic and heterocyclic VOCs such as toluene, p-xylene and indole onto pristine/defected nanographene (with and without dopants) are investigated using density functional theory (DFT). Adsorption of indole is higher (-0.544 to -1.786 eV) in pristine/defected nanographene (with and without dopant) than p-xylene and toluene. The reactivity of defect on adsorption of VOCs is found high for indole with defected nanographene (DG) and toluene with DG-N indicating the influence of sheet type for adsorption rely on the type of the VOCs adsorbate. The charge transfer and type of interaction between the sheet and VOCs are interpreted using Hirshfeld charge analysis, QTAIM and RDG analysis. The influence of VOCs adsorption is high on the electronegativity and electrophilicity index of the pristine/defected nanographene whereas energy gap and hardness show less influence. The noticeable changes in the TDOS and energy gap on adsorption of VOCs with respect to the type of sheet infers that the doped defected sheet have high affinity than the pristine sheet moreover, the suitable sheet for adsorption of VOCs depends on the type of VOCs adsorbate.

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