Engineering porous 2D materials for electrocatalytic small-molecule oxidation in decarbonized energy systems

Abstract Porous two-dimensional (2D) materials have emerged as promising electrocatalysts for small-molecule electrooxidation, including water, alcohol, urea, and formic acid oxidation, which underpin decarbonized energy systems through hydrogen generation, chemical valorization, and pollutant removal. Their high surface area, tunable electronic properties, and enhanced mass transport enable improved catalytic activity, selectivity, and kinetics, yet challenges such as structural instability, catalyst deactivation, and limited mechanistic understanding hinder broader application. While previous studies have emphasized compositional tuning and performance evaluation, a systematic understanding of how porosity, defect engineering, and interlayer interactions regulate electrooxidation efficiency and durability across different small molecules remains insufficient. This review provides a comprehensive evaluation of porous 2D materials in small-molecule electrooxidation, focusing on structure–activity relationships and catalytic mechanisms. Special attention is given to pore architecture, surface defects, electronic configurations, and interlayer coupling in governing adsorption behavior, charge transfer, and intermediate evolution. Porous 2D materials are classified into oxides and their derivatives, hydroxides, sulfides, phosphides, carbides, nitrides, and other emerging systems, with a critical assessment of their catalytic pathways, electronic features, and electrochemical stability. By elucidating reaction-specific structure–performance correlations, this review establishes a unified framework for rational design of porous 2D electrocatalysts in small-molecule electrooxidation.