Nanoparticle Collision Electrocatalysis: From Fundamental to Electrocatalytic Applications

With the rapid development of nano‐catalysts in the field of electrocatalysis, constructing highly active catalysts for energy conversion has become a major research focus. Conventional ensemble electrocatalysis often suffers from limited exposure of catalytic sites due to assembly or coverage, resulting in reduced utilization of active sites. In contrast, nanoparticle collision electrocatalysis (NCE), through the freely diffusive collisions of individual nanoparticles onto an ultramicroelectrode, creates a significantly greater number of accessible reaction sites, exhibiting superior electrocatalytic activity. In this review, the study begins by outlining the fundamentals of NCE, including its collision electrocatalytic mechanism and enhanced strategies. In the section on collision electrocatalytic mechanism, NCE is systematically compared with conventional ensemble electrocatalysis to highlight the advantages of NCE. Subsequently, in the discussion of enhanced strategies, the roles of ultrasonic dispersion and the integration of hydrodynamic flow within confined microchannels as effective means to improve collision frequency and catalytic performance are presented. Next, the study discusses its applications in electrochemical reactions such as the hydrogen evolution reaction, oxygen reduction reaction, methanol oxidation reaction, and hydrogen peroxide reduction reaction. Finally, a perspective on future research directions, aiming to offer strategic guidance for the continued development of NCE in the field of electrocatalysis is provided.