LAUSR

Most transparent conducting oxides (TCOs) exhibit n-type conductivity and are difficult to dope into p-type. Therefore, the development of efficient p-type TCOs is challenging. ZnRh2O4 spinel has been recognized as a potential p-type TCOs. However, the source of its p-type conductivity has not been elucidated. In this study, we used hybrid density functional calculations to investigate the energetics and electronic properties of native defects in ZnRh2O4, including vacancies, interstitials, and cation antisites. We found that all acceptor-type defects including Zn vacancies, Zn antisites, and Rh vacancies acted as deep centers. Charge neutrality analysis suggested that undoped ZnRh2O4 may behave as a p-type semiconductor with hole concentrations of 1018–1019 cm−3 under the extreme O-rich/Rh-poor growth condition in which ZnRh has a low formation energy and acts as the major source of hole carriers. However, under realistic growth conditions, the experimentally determined hole concentration significantly exceeds that which is calculated. Our results suggest that native point defects are unlikely to be responsible for the high hole concentrations observed in ZnRh2O4 spinel.