Emerging p-Block Metal-Based Electrocatalysts for Energy Conversion.

P-block metal-based catalysts are an emerging, effective, and sustainable alternative to precious metal electrocatalysts for energy conversion. These p-block-based materials exhibit unique characteristics, such as oxophilicity, weak hydrogen adsorption, and flexible electronic tuning, which rival those of Pt-group metals. Several morphologies (single-atom catalysts, pure metals, alloys, compounds, and doped systems) have achieved remarkable catalytic efficiencies and selectivity utilizing p-block metals. Recent advances have focused on tailoring the electronic band, surface morphology, and coordination environments, significantly enhancing catalytic stability and activity. Mechanistic studies highlight deviations from traditional d-band scaling relationships, offering novel design strategies for reaction-specific optimization. However, challenges remain. Achieving industrially relevant current densities, long-term stability, and scalable synthesis remains troublesome. This review synthesizes recent progress in p-block metal-based electrocatalysts across various morphologies to identify performance and mechanistic trends for energy conversion applications (e.g., oxygen reduction, nitrate reduction, and carbon dioxide reduction reactions). Critical research directions are identified, and fundamental gaps in p-block metal research are discussed. By establishing the core understanding, future research can focus on untapping the potential of p-block metals for next-generation electrocatalysts.