Computationally driven high-throughput identification of CaTe and Li3Sb as promising candidates for high-mobility p -type transparent conducting materials

High-performance $p$-type transparent conducting materials (TCMs) must exhibit a rare combination of properties including high mobility, transparency, and $p$-type dopability. The development of high-mobility/conductivity $p$-type TCMs is necessary for many applications such as solar cells or transparent electronic devices. Oxides have been traditionally considered as the most promising chemical space to dig out novel $p$-type TCMs. However, nonoxides might perform better than traditional $p$-type TCMs (oxides) in terms of mobility. We report on a high-throughput computational search for nonoxide $p$-type TCMs from a large data set of more than 30 000 compounds which identified CaTe and ${\mathrm{Li}}_{3}\mathrm{Sb}$ as very good candidates for high-mobility $p$-type TCMs. From our calculations, both compounds are expected to be $p$-type dopable: intrinsically for ${\mathrm{Li}}_{3}\mathrm{Sb}$ while CaTe would require extrinsic doping. Using electron-phonon computations, we estimate hole mobilities at room temperature to be about 20 and $70\phantom{\rule{0.28em}{0ex}}{\mathrm{cm}}^{2}/\mathrm{V}\phantom{\rule{0.28em}{0ex}}\mathrm{s}$ for CaTe and ${\mathrm{Li}}_{3}\mathrm{Sb}$, respectively. These are ``upper bound'' values as only scattering with phonons is taken into account. The computed hole mobility for ${\mathrm{Li}}_{3}\mathrm{Sb}$ is quite exceptional and comparable with the electron mobility in the best $n$-type TCMs.