High-entropy materials for electrocatalytic oxygen reduction reaction

Abstract

High-entropy materials (HEMs) have garnered significant attention in the field of catalysis due to their highly tunable compositions, complex yet advantageous electronic structures, abundant active sites, and exceptional physicochemical properties. Despite these promising attributes, a limited fundamental understanding of their properties continues to hinder their broader application, particularly in the electrocatalytic oxygen reduction reaction (ORR). This review provides a comprehensive overview of recent advancements in HEMs for ORR, beginning with an introduction to diverse classes of high-entropy systems—including high-entropy alloys, intermetallics, ceramics, and emerging single-atom configurations. It then delves into the underlying structure–property correlations within these systems, highlighting how entropy-driven design strategies influence their electrocatalytic behavior. Subsequently, the latest progress in applying various high-entropy systems to the ORR is critically analyzed, with a particular emphasis on elucidating the structure–activity relationships that govern catalytic performance. Finally, we outline key challenges and future directions, offering perspectives on the rational design of next-generation high-entropy materials for electrocatalytic ORR and related applications.