Exploring the impact of halide composition on stability and power conversion efficiency in all-inorganic perovskite solar cells

All-inorganic perovskite solar cells (AI-PSCs) are emerging as a promising alternative to organic–inorganic hybrid perovskite solar cells (OIH-PSCs), primarily due to their superior stability and enhanced tolerance to higher temperatures. Despite being a relatively recent focus of research within the perovskite solar cell (PSC) domain, AI-PSCs have demonstrated significant potential, notably in terms of efficiency and durability. However, the power conversion efficiency (PCE) of AI-PSCs, while impressive, has yet to surpass that of OIH-PSCs, highlighting a critical area for further improvement. To date, the PCE of AI-PSCs has reached over 21%, with a rapidly growing body of research contributing to this advancement. This review paper comprehensively summarizes the critical aspects influencing AI-PSC performance, including the fundamentals of crystal structure and its impact on stability, device architecture enhancements to boost PCE, and the role of halide composition in optimizing both stability and efficiency. Specifically, we delve into how halide compositions affect the growth and stability of perovskite at both bulk and interface levels, leading to improved charge carrier dynamics. Finally, we discuss the future outlook and potential of AI-PSCs, outlining a clear path towards their commercial viability.