Native Defect Engineering in CuInTe2
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2020-12-16 |
| Journal | Chemistry of Materials |
| Authors | Jesse Adamczyk, LĂdia C. Gomes, Jiaxing Qu, Grace A. Rome, Samantha M. Baumann |
| Institutions | Colorado School of Mines, University of Illinois Urbana-Champaign |
| Citations | 34 |
Abstract
Section titled âAbstractâTernary diamond-like semiconductors, such as CuInTe2, are known to exhibit promising p-type thermoelectric performance. However, the interplay between growth conditions, native defects, and thermoelectric properties have limited their realization. First-principles calculations of CuInTe2 indicate that the electronic properties are controlled by three dominant defects: VCu, CuIn, and InCu. The combination of these low-energy defects with significant elemental chemical potential phase space for CuInTe2 yields a broad phase width. To validate these calculations, polycrystalline, bulk samples were prepared and characterized for their structural and thermoelectric properties as a function of stoichiometry. Collectively, the off-stoichiometric samples show a range of carrier concentrations that span 5 orders of magnitude (1015 to 1019 h+ cm-3). Mobility of the off-stoichiometric samples suggests that copper vacancies act as strongly scattering point-defect sites, while the other native defects scatter less strongly. Such vacancy scattering extends to the thermal conductivity where a reduction in ÎșL is observed and contributes to enhanced thermoelectric performance. Understanding and controlling the native defects in CuInTe2 provides a route toward n-type dopability as well as rational optimization of the p-type material.