Effective Donor Dopants for Lead Halide Perovskites

Abstract

Chemical doping of lead halide perovskites remains challenging. Here, donor dopants in CsPbBr3 and other perovskites are calculated using hybrid density functional theory including spin–orbit coupling. In agreement with previous work, bismuth dopants incorporating on the Pb site are deep donors, as are antimony dopants, since their p orbitals give rise to midgap states. Furthermore, the s orbitals of gallium dopants lie deep in the CsPbBr3 band gap, also leading to deep defect behavior. In contrast, the group 3 elements scandium and yttrium do not give rise to such midgap states and are shallow donors when incorporating on the Pb site. These donors are stable relative to other configurations and have modest formation energies. Analogous behavior is found in FAPbI3 and CsPbCl3, indicating that n-type conductivity could be achieved in lead halide perovskites with Y and Sc dopants.