Stability challenges of electrocatalytic oxygen evolution reaction: From mechanistic understanding to reactor design

Summary The electrochemical synthesis of chemicals and fuel feedstocks has been demonstrated to be a sustainable and "green" alternative to traditional chemical engineering, where oxygen evolution reaction (OER) plays a vital role in coupling with various cathodic reactions. While tremendous attention, involving both research and review topics, has been focused on pushing the limit of OER catalysts' activity, the long-term stability of OER catalysts, which may play an even more important role in large-scale electrolysis industrialization, has been much less emphasized. Until this point, few systematic strategies for developing OER catalysts with industrially relevant durability have been reported. In this review, critical mechanisms that could influence OER stability are summarized, including surface reconstruction, lattice oxygen evolution, and the dissolution-redeposition process of catalysts. Moreover, to bridge the gap between lab-scale OER tests and large-scale electrocatalysis applications, stability considerations in electrolyzer design for long-term operation are also discussed in detail. This review provides catalyst and reactor design principles for overcoming OER stability challenges and will focus more attention from the field on the great importance of OER stability as well as future large-scale electrocatalysis applications.