Defect chemistry for extrinsic doping in ductile semiconductor α-Ag_(2)S  

作　　者：Hexige Wuliji Kunpeng Zhao Huirong Jing Runxin Ouyang Yu Yang Tian-Ran Wei Hong Zhu Xun Shi 

机构地区：[1]State Key Laboratory of Metal Matrix Composites,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai,200240,China [2]University of Michigan-Shanghai Jiao Tong University Joint Institute,Shanghai Jiao Tong University,Shanghai,200240,China [3]State Key Laboratory of High Performance Ceramics and Superfine Microstructure,Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai,200050,China

出　　处：《Journal of Materiomics》2024年第6期1270-1278,共9页无机材料学学报（英文）

基　　金：This work was supported by the National Natural Science Foundation of China(No.52372209 and 52232010);the Shanghai Pilot Program for Basic Research-Chinese Academy of Science,Shanghai Branch(JCYJ-SHFY-2022-002)。

摘　　要：As a new type of inorganic ductile semiconductor,silver sulfide(α-Ag_(2)S)has garnered a plethora of interests in recent years due to its promising applications in flexible electronics.However,the lack of detailed defect calculations and chemical intuition has largely hindered the optimization of material's performance.In this study,we systematically investigate the defect chemistry of extrinsic doping inα-Ag_(2)S using first-principles calculations.We computationally examine a broad suite of 17 dopants and find that all aliovalent elements have extremely low doping limits(<0.002%)in α-Ag_(2)S,rendering them ineffective in tuning the electron concentrations.In contrast,the isovalent elements Se and Te have relatively high doping limits,being consistent with the experimental observations.While the dopant Se or Te itself does not provide additional electrons,its introduction has a significant impact on the band gap,the band-edge position,and especially the formation energy of Ag interstitials,which effectively improve the electron concentrations by 2–3 orders of magnitudes.The size effects of Se and Te doping are responsible for the more favorable Ag interstitials in Ag_(2)S_(0.875)Se_(0.125) and Ag_(2)S_(0.875)Te_(0.125) with respect to pristine Ag2S.This work serves as a theoretical foundation for the rational design of Ag_(2)S-based functional materials.

关 键 词：Defect chemistry Extrinsic doping THERMOELECTRIC Silver sulfide FIRST-PRINCIPLES 

分 类 号：TQ17[化学工程—硅酸盐工业]