Clarifying the degradation process of luminescent inorganic perovskite nanocrystals

Metal halide perovskites have emerged as highly promising materials for a range of optoelectronic applications. However, their sensitivity to environmental factors, particularly air moisture, presents significant challenges for both reliable research and commercialization. Moisture-induced degradation is a major issue due to the ionic nature of perovskites, which significantly impacts their luminescent properties. Despite extensive research efforts focusing on device applications, a comprehensive understanding of the degradation mechanisms in perovskites remains limited, largely due to their intrinsic ionic characteristics. In this work, we perform an in-depth analysis of the degradation process in perovskite nanocrystals (NCs) synthesized with varying reaction times, exploring the correlation between their optical and structural properties. Our findings reveal that perovskite NCs with larger crystal sizes exhibit greater stability in ambient air, attributed to their lower surface-to-volume ratio. These insights offer a deeper understanding of the relationship between perovskite NC degradation and their optical performance, contributing to advancements in the field of perovskite-based light-emitting technologies. The size-dependent degradation process of inorganic CsPbBr 3 perovskite nanocrystals in ambient air is revealed with structural and optical analysis upon long term air exposure.