Defect engineering and alloying strategies for tailoring thermoelectric behavior in GeTe and its alloys

Chen, Qiyong1; Yang, Cheng1; Xing, Tong2; Xi, Jinyang1; Zhang, Wenqing3; Yang, Jiong1; Xi, Lili1

2025

10.1016/j.jmat.2024.01.007

JOURNAL OF MATERIOMICS   影响因子和分区

2352-8478

GeTe exhibits excellent p-type medium-temperature thermoelectric properties with low toxicity and good mechanical characteristics, making it highly promising for development in the thermoelectric field. However, GeTe is prone to producing Ge vacancies, leading to high p-type carrier concentration, which results in elevated electronic thermal conductivity and a low Seebeck coefficient. This study systematically analyzes intrinsic and extrinsic defects in GeTe and its alloys, focusing on reducing p-type carrier concentration through first-principles calculations. The results reveal that substituting Ge-sites with Bi (BiGe) yields lower donor defect formation energy, effectively reducing p-type carrier concentration of GeTe and its alloys compared to other elemental doping. Additionally, alloying with certain elements, such as Pb, proves favorable for decreased p-type carrier concentration due to lowered energy levels of valence band maximum (VBM). Inspired by this, screening divalent elements for alloying on Ge-sites reveals that Sr, Ba, Eu, and Yb substantially reduce the VBM of GeTe. Further calculations for Ba and Yb-alloyed GeTe confirm changes in formation energies for donor (favorable) and acceptor (unfavorable) defects. Our work provides a systematic investigation of intrinsic and various extrinsic doping defects in GeTe and its alloys, shedding light on possible strategies of optimizing carrier concentration in these compounds. (c) 2024 The Authors. Published by Elsevier B.V. on behalf of The Chinese Ceramic Society. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

GeTe-Based thermoelectric material Intrinsic and extrinsic defect Band alignment

SCI

英语

其他

Natural Science Foundation of China["52172216","92163212"] ; National Key Research and Development Program of China[2021YFB350220]

Chemistry ; Materials Science ; Physics

Chemistry, Physical ; Materials Science, Multidisciplinary ; Physics, Applied

WOS:001303014700001

ELSEVIER

Web of Science

1.Shanghai Univ, Mat Genome Inst, Shanghai 200444, Peoples R China
2.Chinese Acad Sci, Shanghai Inst Ceram, Shanghai 200050, Peoples R China
3.Southern Univ Sci & Technol, Dept Mat Sci & Engn, Shenzhen 518055, Guangdong, Peoples R China

Chen, Qiyong,Yang, Cheng,Xing, Tong,et al. Defect engineering and alloying strategies for tailoring thermoelectric behavior in GeTe and its alloys[J]. JOURNAL OF MATERIOMICS,2025,11(1).

Chen, Qiyong.,Yang, Cheng.,Xing, Tong.,Xi, Jinyang.,Zhang, Wenqing.,...&Xi, Lili.(2025).Defect engineering and alloying strategies for tailoring thermoelectric behavior in GeTe and its alloys.JOURNAL OF MATERIOMICS,11(1).

Chen, Qiyong,et al."Defect engineering and alloying strategies for tailoring thermoelectric behavior in GeTe and its alloys".JOURNAL OF MATERIOMICS 11.1(2025).