Microelectrochemical investigation of electrocatalytic hydrogen evolution reaction

Abstract

Electrocatalytic hydrogen evolution reaction (HER), as a green and sustainable method of hydrogen production, has attracted wide attention in recent years. Designing electrocatalysts with high efficiency, low-cost and stability for HER is becoming increasingly promising and feasible. The emerging microelectrochemical investigation has proven to be a highly effective tool in uncovering complex catalytic mechanism, particularly in HER of single-entity nanocatalysts. Among the various microelectrochemical methods, ultramicroelectrode (UME) and on-chip electrochemical microcell (OCEM) are mostly widely regarded. Both techniques have been extensively employed to analysis the HER process of single-entity nanomaterials, giving unique perspectives inaccessible to conventional electrochemical methods. This review outlines the principles and compares the similarities and differences among UME, OCEM and conventional electrochemical methods. The applications of UME and OCEM investigation of specific nanocatalyts, especially 2D materials, are comprehensively reviewed. Finally, challenges and outlook of microelectrochemical methods in electrocatalysis and beyond are discussed.