Recently, lead chloride perovskites represented by $\mathrm{CsPb}{\mathrm{Cl}}_3$ have been theoretically predicted to be ideal $p$-type transparent conductors and hence have attracted a lot of attention. However, experimentally, these materials have long been known to be insulators that can hardly be converted to $p$-type conductors by extrinsic doping. In this work, we systematically reevaluate the $p$-type dopability of lead chloride perovskites by density functional theory calculations. We find that the previously predicted dopability is due to an overestimation caused by the functional employed that gives an unreasonable high-lying valence band maximum. The hybrid functional with an optimized mixing parameter and the inclusion of spin-orbit coupling gives a suitable description of the band edge positions and thus a better assessment of the dopability. Our defect calculations suggest that lead chloride perovskites are intrinsically insulating and can hardly be converted to $p$-type conductors due to the lack of effective dopants, in agreement with the experimental observations. Our results highlight the importance of the suitable description of band edge positions on the prediction of defect properties and dopability of semiconductors.

• Received 26 May 2020
• Revised 6 September 2020
• Accepted 19 October 2020

DOI:https://doi.org/10.1103/PhysRevMaterials.4.115201