Digitala Vetenskapliga Arkivet

Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Experimental and Theoretical Core Level and Valence Band Analysis of Clean Perovskite Single Crystal Surfaces
Stockholm University, Faculty of Science, Department of Physics.
Stockholm University, Faculty of Science, Department of Physics.
Show others and affiliations
Number of Authors: 122022 (English)In: Small, ISSN 1613-6810, E-ISSN 1613-6829, Vol. 18, no 13, article id 2106450Article in journal (Refereed) Published
Abstract [en]

A detailed understanding of the surface and interface properties of lead halide perovskites is of interest for several applications, in which these materials may be used. To develop this understanding, the study of clean crystalline surfaces can be an important stepping stone. In this work, the surface properties and electronic structure of two different perovskite single crystal compositions (MAPbI3 and CsxFA1–xPbI3) are investigated using synchrotron-based soft X-ray photoelectron spectroscopy (PES), molecular dynamics simulations, and density functional theory. The use of synchrotron-based soft X-ray PES enables high surface sensitivity and nondestructive depth-profiling. Core level and valence band spectra of the single crystals are presented. The authors find two carbon 1s contributions at the surface of MAPbI3 and assign these to MA+ ions in an MAI-terminated surface and to MA+ ions below the surface. It is estimated that the surface is predominantly MAI-terminated but up to 30% of the surface can be PbI2-terminated. The results presented here can serve as reference spectra for photoelectron spectroscopy investigations of technologically relevant polycrystalline thin films, and the findings can be utilized to further optimize the design of device interfaces.

Place, publisher, year, edition, pages
2022. Vol. 18, no 13, article id 2106450
Keywords [en]
molecular dynamics, perovskite single crystals, soft X-ray photoelectron spectroscopy, synchrotron radiation, Z+1 calculation
National Category
Atom and Molecular Physics and Optics
Identifiers
URN: urn:nbn:se:su:diva-202287DOI: 10.1002/smll.202106450ISI: 000751394300001PubMedID: 35122466Scopus ID: 2-s2.0-85124454289OAI: oai:DiVA.org:su-202287DiVA, id: diva2:1640041
Available from: 2022-02-23 Created: 2022-02-23 Last updated: 2022-11-29Bibliographically approved
In thesis
1. In pursuit of next generation photovoltaics: An electronic structure study of emerging solar cell materials
Open this publication in new window or tab >>In pursuit of next generation photovoltaics: An electronic structure study of emerging solar cell materials
2022 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The development of a new generation of photovoltaic technologies is an important task in order to increase the production of clean energy. Perovskite solar cells, with an exceptionally rapid development over the last decade, have transformed into perhaps the most promising candidate to provide a low-cost alternative to conventional cells. While having excellent efficiency, the most successful category of photovoltaic perovskites, the class of hybrid lead-halide perovskites, suffers from poor stability in ambient conditions and gives rise to potential health concerns due to lead toxicity. Because of these issues, studies yielding a better understanding of lead-based perovskites and investigations of new, lead-free materials are likely meaningful steps towards better and more competitive solar cells. This thesis contains studies about established lead-based perovskites, CH3NH3PbI3 and CH(NH2)2PbI3, as well as the lead-free alternatives AgBi2I7 and Cs2AgBiI6. The main method employed is electronic structure calculations through density functional theory under periodic boundary conditions including band structure calculations and projected density of states. A particular focus is given to systems with mixed anion and related effects on the electronic structure.

Place, publisher, year, edition, pages
Stockholm: Department of Physics, Stockholm University, 2022. p. 74
Keywords
Solar cells, computational physics, density functional theory, electronic structure, molecular dynamics, Solceller, beräkningsfysik, täthetsfunktionalteori, elektronstruktur, molekyldynamik
National Category
Atom and Molecular Physics and Optics
Research subject
Theoretical Physics
Identifiers
urn:nbn:se:su:diva-202839 (URN)978-91-7911-818-1 (ISBN)978-91-7911-819-8 (ISBN)
Public defence
2022-04-29, room FB42, AlbaNova universitetscentrum, Roslagstullsbacken 21, Stockholm, 10:00 (Swedish)
Opponent
Supervisors
Available from: 2022-04-06 Created: 2022-03-15 Last updated: 2022-03-25Bibliographically approved
2. Modeling hybrid halide perovskites for solar cell applications: Simulations of electronic structure and X-ray spectroscopy
Open this publication in new window or tab >>Modeling hybrid halide perovskites for solar cell applications: Simulations of electronic structure and X-ray spectroscopy
2022 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Over the past 13 years, perovskites have become a very promising candidate in the search for cheap and effective photovoltaic materials for solar cells.  Perovskite solar cell power conversion efficiency has increased from 3.8% in 2009 to over 25% by late 2022, rivaling that of crystalline silicon cells, and there are a variety of potential chemical compositions that provide a range of materials to investigate.  However, there are still questions about the specific role of all the different chemical components in the material and how they influence its efficiency.  This thesis aims to investigate the effect of material composition and structure through electronic structure calculations and theoretical X-ray absorption and X-ray photoelectron spectroscopy, with comparison to experimental spectra.  Herein, studies on the prototypical hybrid halide perovskite methylammonium lead triiodide (CH3NH3PbI3) are presented and compared among materials with various differences: structural/elemental changes in the case of its precursor methylammonium iodide (CH3NH3I), halide substitution in the case of methylammonium lead tribromide (CH3NH3PbBr3), or organic cation substitution in the case of formamidinium lead triiodide (CH(NH2)2PbI3).

Place, publisher, year, edition, pages
Stockholm: Department of Physics, Stockholm University, 2022. p. 54
Keywords
Solar cells, perovskites, computational chemistry, simulations, electronic structure, density functional theory, X-ray spectroscopy
National Category
Atom and Molecular Physics and Optics
Research subject
Chemical Physics
Identifiers
urn:nbn:se:su:diva-211949 (URN)978-91-8014-114-7 (ISBN)978-91-8014-115-4 (ISBN)
Public defence
2023-01-13, Lärosal 14, Albano Hus 2, Albanovägen 18, Stockholm, 10:00 (English)
Opponent
Supervisors
Funder
Swedish Energy Agency, 2017-006797
Available from: 2022-12-20 Created: 2022-11-29 Last updated: 2022-12-12Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textPubMedScopus

Search in DiVA

By author/editor
Sterling, Cody M.Gangan, AbhijeetErbing, AxelKamal, ChinnathambiMan, Gabriel J.Rensmo, HåkanOdelius, Michael
By organisation
Department of Physics
In the same journal
Small
Atom and Molecular Physics and Optics

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 52 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf