High-entropy alloys for electrocatalysis: From fundamental properties to rational design and energy applications

Electrochemical energy conversion technologies are central to addressing global energy shortages and environmental pollution, yet their practical efficiency is often limited by sluggish reaction kinetics and the reliance on noble-metal-based catalysts. High-entropy alloys (HEAs), consisting of five or more elements in nearly equiatomic proportions, have garnered growing attention due to their distinctive properties, including exceptional strength, high hardness, excellent ductility, and corrosion resistance. In this review, we systematically examine the roles of HEAs in electrocatalytic energy conversion, with a particular focus on how their phase structures and core effects govern catalytic activity, selectivity, and durability. We further summarize recent advances in HEA electrocatalyst synthesis and optimization, addressing challenges in scalable compositional control, stability under harsh conditions, and atomic-level regulation of defects and lattice strain. Finally, we outline future directions toward next-generation HEAs catalysts, highlighting opportunities in theory-experiment integration, advanced in situ characterization, large-scale synthesis with uniform composition, and quantitative structure-performance relationships. We anticipate that this review will stimulate further exploration and development of HEAs for electrochemical applications. • Systematically summarizes the fundamental properties of high-entropy alloys (HEAs) for electrocatalysis, encompassing phase structures and four key governing effects. • Comprehensively elucidates four core regulation strategies, integrating intrinsic mechanisms with representative experimental evidence. • Highlights the superior electrocatalytic performance of HEAs in critical reactions and practical application scenarios, benchmarking against conventional noble-metal-based catalysts • Provides systematic guidelines for the rational design and scalable deployment of high-performance HEAs electrocatalysts, addressing the urgent need for clean energy conversion technologies.