Construction and Structure Tailoring of Versatile Metal Halide Perovskite Composites for Photocatalysis

Photocatalytic technologies are essential for addressing energy and environmental challenges. Metal halide perovskites (MHPs) have emerged as promising photocatalysts owing to their adjustable bandgaps, high efficiency, and broad visible-light absorption capabilities. However, despite their potential, MHPs encounter obstacles that impede their effective use. These challenges include the necessity to maintain stability in aqueous and oxygen-rich environments as well as at elevated temperatures. Moreover, issues such as electron-hole recombination and limited oxidation activity during photocatalytic processes present significant hurdles that must be overcome for the successful application of MHPs. This review addresses the latest advancements in the application of MHPs for photocatalytic tasks, such as hydrogen production, carbon dioxide reduction, degradation of organic contaminants, and removal of nitrogen oxides. The first part of the review addresses the basic principles of photocatalysis, the crystalline structures, coordination environments, and distinguishing features of MHP photocatalysts. A range of strategies has been investigated to improve the performance of MHP photocatalysts and address challenges such as low stability, excessive charge recombination, and limited active sites. These strategies involve controlling morphology, forming heterojunctions, modifying surfaces or interfaces, and encapsulating the materials. The paper further examines the ongoing challenges and future prospects of MHP photocatalysts, highlighting their promising potential and significant role in a wide range of photocatalytic applications. Highlights Structures, properties, coordination environments, and basic principles of metal halide perovskite photocatalysts. Comprehensive summary of efficient photocatalytic strategies activity and stability of metal halide perovskites. Current progresses in the photocatalytic H₂ generation, CO₂ reduction, organics degradation, and NO_x remediation. Current challenges and future prospective of metal halide perovskite as efficient photocatalysts.