Simultaneous Enhancement of Thermopower and Electrical Conductivity through Isovalent Substitution of Cerium in Bismuth Selenide Thermoelectric Materials

Jamal Deen Musah, Xiao Yanjun, A. M. Ilyas, Travis G. Novak, Seokwoo Jeon, Clement Arava, S. V. Novikov, D. S. Nikulin, Wei Xu, Liyao Liu, Asaduzzaman Md, Kwok Ho Lam, Xianfeng Chen, Chi Man Lawrence Wu, Vellaisamy A.L. Roy

Research output: Journal article publicationJournal articleAcademic researchpeer-review

3 Citations (Scopus)

Abstract

It is challenging to achieve highly efficient thermoelectric materials due to the conflicts between thermopower (Seebeck coefficient) and electrical conductivity. These parameters are the core factors defining the thermoelectric property of any material. Here, we report the use of isovalent substitution as a tool to decouple the interdependency of the Seebeck coefficient and the electrical properties of cerium-doped bismuth selenide thermoelectric material. With this strategy, we can achieve a simultaneous increase in both the electrical conductivity and the Seebeck coefficient of the material by tuning the concentration of cerium doping, due to formation of neutral impurities and consequently the improvement of carrier mobility. Our theoretical calculation reveals a downward shift of the valence band with cerium concentration, which influences the thermoelectric enhancement of the synthesized materials. Finally, an order of magnitude enhancement of the figure of merit is obtained due to isovalent substitution, thus providing a new avenue for enhancing the thermoelectric performance of materials.

Original languageEnglish
Pages (from-to)44026-44035
Number of pages10
JournalACS Applied Materials and Interfaces
Volume11
Issue number47
DOIs
Publication statusPublished - 27 Nov 2019

Keywords

  • isovalent substitution
  • metal chalcogenides
  • power factor (PF)
  • simultaneous enhancement
  • thermoelectric (TE)

ASJC Scopus subject areas

  • Materials Science(all)

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