Contrasting strategies of optimizing carrier concentration in bulk InSe for enhanced thermoelectric performance  

作　　者：Hao-Nan Shi Shu-Lin Bai Yu-Ping Wang Li-Zhong Su Qian Cao Cheng Chang Li-Dong Zhao 

机构地区：[1]School of Materials Science and Engineering,Beihang University,Beijing 100191,China [2]School of Materials Science and Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China [3]Huabei Cooling Device Co.Ltd.,Hebei 065400,China

出　　处：《Rare Metals》2024年第9期4425-4432,共8页稀有金属（英文版）

基　　金：supported by the National Science Fund for Distinguished Young Scholars(No.51925101);the Tencent Xplorer Prize,the National Natural Science Foundation of China(Nos.52371208,52250090,52002042,51772012,51571007and 12374023);Beijing Municipal Natural Science Foundation(JQ18004);the 111 Project(B17002)。

摘　　要：Indium selenide(InSe),as a wide-bandgap semiconductor,has received extensive attention in the flexible electronics field in recent years due to its exceptional plasticity and promising thermoelectric performance.However,the low carrier concentration severely limits its thermoelectric performance improvement.In this work,we conducted contrasting strategies that can be employed to increase the carrier concentration of InSe,including bandgap narrowing and heterovalent doping.Specifically,the carrier concentration initially increases as a result of the reduced bandgap upon Te alloying and then slightly decreases due to the weak electronegativity of Te.Whereas Br doping realizes high carrier concentration by pushing the Fermi level into the conduction bands and activating the multiple bands.On the other hand,both Te and Br obviously suppress the thermal conductivity due to the point defect scattering.By contrast,Br doping realizes a higher thermoelectric performance with a maximum ZT of~0.13 at 773 K benefiting from the better optimization of carrier concentration.This work elucidates the strategies for enhancing carrier concentration at anion sites and demonstrates the high efficiency of halogen doping in InSe.Moreover,the carrier concentration of InSe is promising to be further optimized,and future work should focus on employing approaches such as cation doping or secondphase compositing.

关 键 词：THERMOELECTRIC INSE Carrier concentration Bandgap Heterovalent doping 

分 类 号：TB34[一般工业技术—材料科学与工程]