Defect chemistry and doping of BiCuSeO. Issue 36 (31st August 2021)

• Record Type: Journal Article
• Authors: Toriyama, Michael Y.; Qu, Jiaxing; Snyder, G. Jeffrey; Gorai, Prashun
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 36(2021)
• Page Start: 20685
• Page End: 20694
• Publication Date: 2021-08-31
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d1ta05112a
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : We explore n-type doping of BiCuSeO, an otherwise well-known p-type thermoelectric material, and find halogens to be the most effective n-type dopants. Abstract : While p-type BiCuSeO is a well-known mid-temperature oxide thermoelectric (TE) material, computations predict that superior TE performance can be realized through n-type doping. In this study, we use first-principles defect calculations to show that Cu vacancies are responsible for the native p-type self doping; yet, we find that BiCuSeO is n-type dopable under Cu-rich growth conditions, where the formation of Cu vacancies is suppressed. We computationally survey a broad suite of 23 dopants and find that only Cl and Br are effective n-type dopants. Therefore, we recommend that future experimental doping efforts utilize phase boundary mapping to optimize the electron concentration and resolve the anomalous p–n–p transitions observed in halogen-doped BiCuSeO. The prospect of n-type doping, as revealed by our defect calculations, paves the path for rational design of BiCuSeO chemical analogues with similar doping behavior and even better TE performance.