Interfacial Engineering of Ti₃C₂T_x -Protected CsPbBr₃ Perovskite Quantum Dots for Enhanced Charge Transport and Superior Hydrogen Evolution Catalysis

Hydrogen from electrochemical water splitting is a green energy carrier, but sluggish HER kinetics necessitate cost-effective alternatives to insufficient Pt-based catalysts. In this respect, efficient, low-cost HER electrocatalysts are crucial for survivable hydrogen production, with inorganic halide perovskites offering variable ionic-electronic conductivity and processability, while MXene provide complementary benefits of high conductivity and abundant active sites. State-of-the-art engineering strategies and characterization techniques of CsPbBr₃@Ti₃C₂T_x hierarchical structure are elucidated, emphasizing how unique crystallographic features and tuneable surface terminations of Ti₃C₂T_x synergistically augment catalytic activity of pristine CsPbBr₃ perovskite quantum dots (PQDs). Subsequently, experimental and theoretical aspects employing CsPbBr₃@Ti₃C₂T_x nanohybrids as efficient HER electrocatalysts are extensively discussed. Electrochemical analysis demonstrated that CsPbBr₃@Ti₃C₂T_x delivered a low onset potential of −231.12 mV following Volmer-Heyrovsky pathway with reduced Tafel slope of 48.04 mV dec⁻¹, indicative of accelerated HER kinetics. The hierarchical structure flaunted supercilious cycling stability compared to CsPbBr₃ PQDs, with the intensified activity emerging from efficient charge ddeliveryat CsPbBr₃/Ti₃C₂T_x interface, ample sites, and low R_ct. These experimental examinations are further corroborated by theoretical calculations, disclosing laudatory Gibbs free energy and enriched total density of states. CsPbBr₃@Ti₃C₂T_x emerge as lucrative, high-performance HER electrocatalysts, where Ti₃C₂T_x reinforced stability and conductivity, offering fa lexible approach for next-generation energy conversion.