Layered Perovskite Materials for Photocatalytic Overall Water Splitting: Recent Advances, Enhanced Strategies, and Future Challenges

ABSTRACT Achieving sustainable energy generation without causing environmental pollution is one of modern society's grand challenges. Photocatalytic overall water splitting (OWS) presents a sustainable option for producing the green energy vector H 2 while eliminating the need for sacrificial agents. However, the selection of appropriate catalysts is essential for the practical viability of this approach. Among various photocatalytic materials, layered perovskites have attracted significant attention due to their compositional flexibility and attractive hybrid electronic band structure. Moreover, their intrinsic layered architecture promotes charge separation, which further enhances photocatalytic performance. Therefore, layered perovskites are considered promising candidates for photocatalytic OWS. Herein, this review classifies and summarizes the research progress of (100)‐, (110)‐, and (111)‐type layered perovskite photocatalysts for OWS. We first introduce the basic principle of photocatalytic OWS, followed by a discussion of the advantages and challenges of employing layered perovskites as OWS photocatalysts. The relevant properties of layered perovskite photocatalysts that influence OWS performance are analyzed. Furthermore, experimental strategies such as doping, composite structure construction, and morphology modulation are comprehensively reviewed to highlight their roles in enhancing photocatalytic efficiency. Finally, current limitations and future research directions for layered perovskite‐based OWS are outlined to guide further developments in this field.