Schottky Defects Suppress Nonradiative Recombination in CH3NH3PbI3 through Charge Localization

Hybrid lead halide perovskites are promising materials for photovoltaic applications due to their exceptional optoelectronic properties. Here, we investigate the impact of Schottky defects─specifically PbI2(VPbI2) and CH3NH3I (VMAI) vacancies─on nonradiative recombination in CH3NH3PbI3 using time-dependent density functional theory and nonadiabatic (NA) molecular dynamics. Our results reveal that Schottky defects do not alter the fundamental bandgap or introduce trap states but instead distort the surrounding lattice, localizing the hole distribution. This reduces the spatial overlap of electron and hole wave functions, weakening NA coupling and increasing intensitieis of high-intensity phonon modes that accelerate dephasing. Consequently, nonradiative recombination lifetimes extend to 2.1 and 2.6 ns for VPbI2 and VMAI, respectively─over double that of pristine CH3NH3PbI3. This work demonstrates the potential of Schottky defects to enhance perovskite solar cell performance by suppressing nonradiative recombination.