Strategies for Designing High-Performance Hydrogen Evolution Reaction Electrocatalysts at Large Current Densities above 1000 mA cm-2

Abstract

The depletion of fossil fuels and rapidly increasing environmental concerns have urgently called for the utilization of clean and sustainable sources for future energy supplies. Hydrogen (H₂) is recognized as a prioritized green resource with little environmental impact to replace traditional fossil fuels. Electrochemical water splitting has become an important method for large-scale green production of hydrogen. The hydrogen evolution reaction (HER) is the cathodic half-reaction of water splitting that can be promoted to produce pure H₂ in large quantities by active electrocatalysts. However, the unsatisfactory performance of HER electrocatalysts cannot follow the extensive requirements of industrial-scale applications, including working efficiently and stably over long periods of time at high current densities (⩾1000 mA cm^-2). In this review, we study the crucial issues when electrocatalysts work at high current densities and summarize several categories of strategies for the design of high-performance HER electrocatalysts. We also discuss the future challenges and opportunities for the development of HER catalysts.

Keywords: composition; design strategy; electrocatalysts; hydrogen evolution reaction; issues; large current density; mechanism; structure.