Electrocatalysts for alkaline water electrolysis at ampere-level current densities: a review

Alkaline water electrolysis is a central technology to produce large-scale green hydrogen, a zero-emission energy carrier. Great progress has been made on electrocatalyst development for alkaline water electrolysis, but the performance is still limited at industrial scale ampere-level current densities. In this review, we summarize the criteria required for the development of electrocatalysts for alkaline water electrolysis at ampere-level current densities, in terms of both activity and stability. The operation parameters needed to be noted when performing water electrolysis at ampere-level current densities conditions are discussed. In addition, the current challenges and future perspectives on the design of efficient and durable electrocatalysts performing at ampere-level current densities are highlighted.