TY - JOUR
T1 - Simultaneous Enhancement of Thermopower and Electrical Conductivity through Isovalent Substitution of Cerium in Bismuth Selenide Thermoelectric Materials
AU - Musah, Jamal Deen
AU - Yanjun, Xiao
AU - Ilyas, A. M.
AU - Novak, Travis G.
AU - Jeon, Seokwoo
AU - Arava, Clement
AU - Novikov, S. V.
AU - Nikulin, D. S.
AU - Xu, Wei
AU - Liu, Liyao
AU - Md, Asaduzzaman
AU - Lam, Kwok Ho
AU - Chen, Xianfeng
AU - Wu, Chi Man Lawrence
AU - Roy, Vellaisamy A.L.
N1 - Publisher Copyright:
Copyright © 2019 American Chemical Society.
PY - 2019/11/27
Y1 - 2019/11/27
N2 - 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.
AB - 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.
KW - isovalent substitution
KW - metal chalcogenides
KW - power factor (PF)
KW - simultaneous enhancement
KW - thermoelectric (TE)
UR - http://www.scopus.com/inward/record.url?scp=85075550554&partnerID=8YFLogxK
U2 - 10.1021/acsami.9b11344
DO - 10.1021/acsami.9b11344
M3 - Article
C2 - 31738515
AN - SCOPUS:85075550554
SN - 1944-8244
VL - 11
SP - 44026
EP - 44035
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 47
ER -