Aliovalent Doping of Lead Halide Perovskites: Exploring the CH₃NH₃PbI₃–(CH₃NH₃)₃Sb₂I₉ Nanocrystalline Phase Space

Lead halide perovskites have attracted significant attention in the past few years due to their outstanding performance in photovoltaic devices. Nanoscale versions of these materials are also good candidates for light emitting devices. In this work, we synthesize perovskite nanocrystals using a surfactant-free method by introducing antimony iodide in the perovskite precursor. Surface-bound (CH₃NH₃)₃Sb₂I₉ layers restrict the growth of CH₃NH₃PbI₃, resulting in CH₃NH₃PbI₃ nanocrystals of about 50 nm in size. Compared to the bulk perovskites, the nanocrystals show stronger photoluminescence. As there are no long-chain organic ligands on the surface that will inhibit the charge transport, these surfactant-free nanocrystals may have better performance in photoelectronic devices