Diverse Perovskite Solar Cells: Progress, Challenges, and Perspectives

Perovskite materials have revolutionized optoelectronics by virtue of their tunable bandgaps, exceptional optoelectronic properties, and structural flexibility. Notably, the state-of-the-art performance of perovskite solar cells has reached 27%, making perovskite materials a promising candidate for next-generation photovoltaic technology. Although numerous reviews regarding perovskite materials have been published, the existing reviews generally focus on individual material systems (e.g., organic–inorganic hybrid perovskites) and specific optimizations in one particular optoelectronic application (e.g., stability engineering for solar cells), lacking a systematic overview of the progress and challenges across diverse perovskite types. This review breaks this limitation by providing a systematic overview of all perovskite categories used in solar cells classified by different criteria, including composition (organic–inorganic hybrid perovskites, all-inorganic perovskites, lead-free perovskites, and metal-free perovskites), dimensionality (3D and low-dimensional perovskitoids), and crystallinity (poly-crystal thin film and single-crystal perovskites). The recent progress and future perspectives for each category of perovskite solar cells are focused on, aiming to establish a holistic roadmap for perovskite solar cells toward technological innovations and industrial viability.