Revealing the In Situ Dynamic Regulation of the Interfacial Microenvironment Induced by Pulsed Electrocatalysis in the Oxygen Reduction Reaction

Pulsed electrocatalysis has emerged as a promising technology to effectively improve reaction kinetics and tailor product selectivity. While most research focuses on the evolution of electrocatalyst active sites, the dynamic response of the interfacial microenvironment during pulsed electrocatalysis still remains unknown. Here, we reveal the in situ dynamic regulation of the interfacial microenvironment induced by pulsed electrocatalysis in the oxygen reduction reaction process, from the interface reactant delivery to intermediate formation dynamics. At the diffusion layer, the coupling of pulsed electrocatalysis and hierarchical pore structure was proven to break the limitation of proton transfer, resulting in favorable H 2 O 2 production kinetics. At the electrode/electrolyte interface, the pulsed electric field would stimulate the cation effect to activate C–*OOH and reduced the reaction energy barrier, giving rise to more favorable *OOH formation thermodynamics. This work provides new insights into exploring in situ regulation of the interfacial microenvironment, which is expected to be extended to different electrochemical processes.