Trends in acceptor dopants for halide perovskites

The halide perovskites, such as cesium lead bromide (CsPbBr₃) and methylammonium lead iodide (MAPI), are expected to be high-performing light emitters, with potential applications including lighting, displays, and quantum information. All of these applications would benefit from having fully controlled electrical conductivity, but it has proven difficult to achieve high p-type carrier concentrations in these materials. In this work, possible acceptor dopants are evaluated in the halide perovskites, using first-principles calculations based on a hybrid functional with spin-orbit coupling. This approach not only leads to accurate predictions for band structure and band offsets, but also provides a better description of dopant properties. We assess here whether acceptor dopants (such as Ag, Na, and Cu) can act as shallow acceptors on the proper substitutional site, and whether other configurations of these impurities might lead to compensation of potential p-type conductivity. Among the dopants considered, sodium and silver are identified as the most promising acceptors for achieving p-type conductivity, and optimum chemical potential conditions for these dopants are identified.