Change search
ReferencesLink to record
Permanent link

Direct link
Fabrication and characterization of nanostructured thermoelectric FexCo1-xSb3
KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.ORCID iD: 0000-0003-0855-5265
KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.ORCID iD: 0000-0001-5380-975X
KTH, School of Information and Communication Technology (ICT), Material Physics (Closed 20120101), Functional Materials, FNM (Closed 20120101).ORCID iD: 0000-0001-5678-5298
Stockholm University.
Show others and affiliations
2015 (English)In: Open Chemistry, ISSN 2391-5420, Vol. 13, no 1, 629-635 p.Article in journal (Refereed) Published
Abstract [en]

A novel synthesis route for the fabrication of p-type nanostructured skutterudite, FexCo1-xSb3 in large quantity is reported. This scalable synthesis route provides nano-engineered material with less impact on the environment compared to conventional synthesis procedures. Several Fe substituted compositions have been synthesized to confirm the feasibility of the process. The process consists of a nano-sized precursor fabrication of iron and cobalt oxalate, and antimony oxides by chemical co-precipitation. Further thermochemical processes result in the formation of iron substituted skutterudites. The nanopowders are compacted by Spark Plasma Sintering (SPS) technique in order to maintain nanostructure. Detailed physicochemical as well as thermoelectric transport properties are evaluated. Results reveal strongly reduced thermal conductivity values compared to conventionally prepared counterparts, due to nanostructuring. P-type characteristic was observed from the Seebeck measurements while electrical conductivity is high and shows metallic behavior. The highest TE figure of merit of 0.25 at 800 K has been achieved, which is strongly enhanced with respect to the mother compound CoSb3. This suggests the promise of the utilized method of fabrication and processing for TE applications with improved performance.

Place, publisher, year, edition, pages
2015. Vol. 13, no 1, 629-635 p.
Keyword [en]
Skutterudite (CoSb3), thermoelectric, iron substituted skutterudite, bottom-up synthesis, SPS
National Category
Materials Chemistry
Research subject
Materials Science and Engineering
URN: urn:nbn:se:kth:diva-160646DOI: 10.1515/chem-2015-0074ISI: 000355403100076OAI: diva2:790825
Swedish Foundation for Strategic Research , EM11-0002EU, FP7, Seventh Framework Programme, 263167

QC 20150312

Available from: 2015-02-25 Created: 2015-02-25 Last updated: 2016-05-03Bibliographically approved
In thesis
1. Nanostructured Bulk Thermoelectrics: Scalable Fabrication Routes, Processing and Evaluation
Open this publication in new window or tab >>Nanostructured Bulk Thermoelectrics: Scalable Fabrication Routes, Processing and Evaluation
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Current fossil fuel based energy sources have a huge shortcoming when one discusses their efficiency. The conversion efficiency of fossil fuel-based technologies is less than 40% in best cases. Therefore, until the renewable energy section is mature enough to handle all the energy demand one has to research and develop the technologies available to harvest the energy from the waste heat generated in fossil fuel-based supply sources. One of these emerging technologies is the use of thermoelectric (TE) devices to achieve this goal, which are solid-state devices capable of directly interconverting between heat and electrical energy. In the past decade there has been a significant scientific and financial investment within the field to enhance their properties and result in time/energy efficient fabrication processes of TE materials and devices for a more sustainable environment.

In this thesis with use of chemical synthesis routes for nanostructured bulk thermoelectric materials iron antimonide (FeSb2), skutterudites (based on general formula of RzMxCo1-xSb3-yNy) and copper selenide (Cu2Se) are developed. These materials are promising candidates for use in thermoelectric generators (TEG) or for sensing applications. Using chemical synthesis routes such as chemical co-precipitation, salt melting in marginal solvents and thermolysis, fabrication of these TE materials with good performance can be performed with high degree of reproducibility, in a much shorter time, and easily scalable manner for industrial processes. The TE figure of merit ZT of these materials is comparable to, or better than their conventional method counterparts to ensure the applicability of these processes in industrial scale.

Finally, through thorough investigation, optimized consolidation parameters were generated for compaction of each family of materials using Spark Plasma Sintering technique (SPS). As each family of TE nanomaterial investigated in this thesis had little to no prior consolidation literature available, specific parameters had to be studied and generated. The aim of studies on compaction parameters were to focus on preservation of the nanostructured features of the powder while reaching a high compaction density to have positive effects on the materials TE figure of merit.

Abstract [sv]

Dagens fossilbränslebaserade energikällor har en enorm brist gällande effektivitet. Effektiviteten av fossilbränslebaserade teknologiers omvandling är mindre än 40 % i bästa fall. Därför tills förnybar energi är mogen nog att hantera alla energibehov, måste man forska och utveckla teknik för att skörda energi från spillvärme i fossilbränslebaserade försörjningskällor. En av dessa nya tekniker är tillämpning av termoelektriska (TE) material för att uppnå målet. Nämnde material är Soldi-State materialer som kan transformera mellan värme och elektrisk energi. Under det senaste decenniet har det pågått en stor vetenskaplig och ekonomisk investering inom området för att förbättra termoelektriska materials egenskaper. Dessutom ville man ta fram tid/energieffektiva TE material och komponenter för en mer hållbar miljö.

I denna avhandling utvecklades och producerades termoelektriska material såsom järn antimonid (FeSb2), skutterudit (baserat på allmänna formeln RzMxCo1-xSb3-YNY) och koppar selenid (Cu2Se) med hjälp av kemiska syntesmetoder. Genom att Använda kemiska syntesmetoder som kemisk samutfällning, salt smältning i marginella lösningsmedel och termolys, kan material med hög grad av reproducerbarhet och ställbar för industriella processer tillverkas.   Termoelektrisk omvandling effektivitet hos uppnådde material är betydligt högre än resultat av andra studier. I och med detta kan man säga att materialet kan användas inom industri.

Slutligen, genom en grundlig undersökning optimerades packningsparametrar som genererades för packning av varje materialgrupp med hjälp av Spark Plasma Sintring teknik (SPS). Eftersom ingen relevant studie finns för varje grupp av termoelektriska nanomaterial som undersökts i denna avhandling, studerades och genererades dessa specifika parametrar. Syftet med studien är att fokusera på bevarande av nanostrukturerade egenskaperna hos pulvret och att samtidigt nå en hög packningstäthet för att ha positiva effekter på materialens termoelektriska omvandlingseffektivitet.

Place, publisher, year, edition, pages
Stockholm, Sweden: KTH Royal Institute of Technology, 2016. x, 34 p.
TRITA-ICT, 2016:10
Thermoelectric, Iron antimonide (FeSb2) Skutterudite, Copper Selenide (Cu2Se), Spark Plasma Sintering (SPS), nanomaterial
National Category
Condensed Matter Physics
Research subject
Materials Science and Engineering; Energy Technology
urn:nbn:se:kth:diva-186124 (URN)978-91-7595-945-0 (ISBN)
Public defence
2016-05-27, Sal C, Isafjordsgatan 22, Kista, 10:00 (English)
Swedish Foundation for Strategic Research , EM11‐0002EU, FP7, Seventh Framework Programme, 263167

QC 20160503

Available from: 2016-05-03 Created: 2016-05-02 Last updated: 2016-05-10Bibliographically approved

Open Access in DiVA

fulltext(1346 kB)130 downloads
File information
File name FULLTEXT01.pdfFile size 1346 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Search in DiVA

By author/editor
Tafti, Mohsen YakshiSaleemi, MohsinToprak, Muhammet SMuhammed, Mamoun
By organisation
Materials- and Nano PhysicsFunctional Materials, FNMFunctional Materials, FNM (Closed 20120101)
Materials Chemistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 130 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 51 hits
ReferencesLink to record
Permanent link

Direct link