Perovskite Quantum Dots as Integrated Light-Driven Catalysts: Unified Advances in Photocatalytic and Photoelectrocatalytic Applications

• Impact of Co²⁺, Pd²⁺, and Zn²⁺ doping on perovskite QD photocatalysis. • Lead-free QDs enhance stability and maintain high photocatalytic activity. • Ligand and MOF/GO encapsulation improve charge separation and durability. • Heterojunctions and cocatalysts boost H₂ evolution and CO₂ reduction. • Challenges of scalable synthesis and long-term operation under real conditions . The growing demand for sustainable solar-driven chemical processes has intensified the search for highly efficient and stable photocatalytic materials. Despite the remarkable optoelectronic properties of conventional semiconductors, their limited defect tolerance, narrow spectral absorption, and instability under aqueous conditions hinder practical applications. Perovskite quantum dots (PQDs) have emerged as a promising alternative, offering tunable bandgaps, strong light absorption, long carrier diffusion lengths, and intrinsic defect tolerance. However, challenges such as moisture sensitivity, photodegradation, and rapid charge recombination have restricted their broader deployment. Recent advances in compositional engineering, surface-ligand optimization, heterostructure construction, and strategic doping have significantly enhanced PQD stability and charge-separation efficiency. These improvements have enabled superior photocatalytic performance in hydrogen evolution, CO₂ reduction, selective organic transformations, and pollutant degradation, as well as enhanced photoelectrocatalytic activity in current-driven systems. This review critically analyzes these strategies, comparing and contrasting different approaches to overcome intrinsic limitations and highlighting how structural, interfacial, and photonic engineering collectively drive high efficiency. By bridging the knowledge gap between fundamental PQD properties and practical applications, this work provides insights into designing next-generation, solar-driven catalytic systems with improved durability and functionality. .