Engineering active sites for electrocatalytic energy conversion reactions

Electrocatalytic energy conversion processes demand precise control of the electronic properties of active sites to overcome slow reaction kinetics and achieve high energy conversion efficiency. This review systematically examines recent developments in active-site engineering from four complementary dimensions. Composition regulation customizes electronic structures via metal doping, defect engineering, and dual-atom site construction. Structural design optimizes stepped surfaces and porous structure to improve mass transport and expose more accessible active sites. Interface modulation utilizes heterogeneous junctions and refined coordination environments to generate synergistic catalytic effects, while operating-environment tuning emphasizes how electrolytes and applied potentials dynamically reshape active-site states. By integrating advanced in situ/operando characterization with theoretical modeling, these strategies provide deeper mechanistic understanding and more principle-driven design guidelines. Coupling these insights with atomic-precision synthesis and artificial intelligence is expected to accelerate the development of next-generation, high-performance electrocatalysts for sustainable energy technologies.