Pulsed Electrochemistry in Water Electrolysis: Catalyst Engineering, Performance Optimization, and Mechanism Elucidation

Pulsed electrochemical technology operates in an unsteady-state mode that rapidly alternates between reaction and recovery states, enabling deep catalyst engineering, dynamic optimization of the catalyst−electrolyte microenvironment, and high-resolution probing of catalytic mechanisms in water electrolysis. Despite these advantages, systematic overview from fundamental research and simulations to industrial applications is lacking. This review introduces the principles and operational parameters of pulsed electrochemical processes, then discusses advances in catalyst engineering, performance optimization, and mechanistic studies. In catalyst engineering, advances include pulse electrodeposition, activation, regeneration, and associated simulations, with emphasis on regulating morphology and composition to enhance intrinsic activity and durability. In performance optimization, the role of pulsed electrochemistry in promoting reaction kinetics is examined, particularly its ability to dynamically optimize the local microenvironment by facilitating ion transport and gas bubble dissipation, as supported by simulation insights. In mechanistic studies, relevant pulse techniques are highlighted, including normal pulse voltammetry for assessing charge storage and mass transfer, and differential pulse voltammetry for probing oxidation state transitions and kinetic competition in hybrid systems. The review also presents advances toward industrial-scale hydrogen production, such as simulation of operating conditions for renewable-powered electrolyzers and developments in high-power pulsed electrolyzers. Finally, current challenges and potential solutions are outlined.