Mapping and characterization of surface-dependent electronic properties and morphological changes in the cubic phase of crystalline perovskite CsPbBr 3

Lead halide perovskites are attracting considerable interest across a wide range of applications, from gas sensors to energy conversion and utilization. Here, the cubic phase of crystalline perovskite CsPbBr 3 is proposed as a probe to shed light on subtle structural and electronic changes that control surface-dependent electronic properties and morphology, using a computational approach based on density functional theory calculations. We carried out first-principles density functional theory calculations to obtain the surface-dependent properties (band structures, density of states, and surface energies) of low Miller-index (001), (110), and (111) surfaces with different terminations of CsPbBr 3 . Additionally, the atomic arrangements and stability of these surfaces were characterized to provide a close match between experimental field-emission scanning electron microscopy images and computational simulations. We demonstrate a practical application of the Wulff construction by leveraging computed surface energies to determine a complete map of available morphologies that are consistent with experimental observations. Our findings reveal how the exposed surfaces on the morphology influence the electronic properties, elucidating the atomic-level synergy between surface-dependent electronic properties and morphological changes in CsPbBr 3 , and providing a theoretical foundation and design principles for enhancing perovskite stability through surface engineering.