ABSTRACT Electrocatalytic technology represents a pivotal pathway for converting low‐value feedstocks into high‐value products, though its practical implementation continues to face fundamental challenges such as sluggish reaction kinetics and high energy barriers. These limitations are increasingly being overcome through multi‐active site (MAS) architectures, which utilize synergistic effects to facilitate multi‐electron transfer processes and establish a new paradigm in catalyst design. This review systematically explores rational design and engineering strategies for MAS structures, covering approaches such as heterostructure construction, dual‐atom site modulation, defect engineering, alloying, and cascade reaction systems, all aimed at improving overall electrocatalytic performance. We further analyze the intrinsic mechanisms responsible for performance breakthroughs in MAS architectures, including their ability to decouple reaction steps, optimize intermediate adsorption, enable electron–proton co‐transfer, and suppress competing side reactions. By integrating advanced characterization techniques with theoretical simulations, this work also reveals key cooperative mechanisms and dynamic reaction pathways, establishes a foundational framework for catalyst refinement, and details applications of multi‐component active sites across major catalytic reactions. Finally, we outline persistent challenges and propose future research directions, offering a systematic theoretical basis for the development of next‐generation electrocatalysts for sustainable energy systems.
Ge et al. (Sun,) studied this question.