Nanocatalyst Design for Long-Term Operation of Proton/Anion Exchange Membrane Water Electrolysis

Long-term catalyst stability is essential for the commercialization of hydrogen generation by electrocatalytic water-splitting. Current research, however, mainly focuses on improving electrode activity of the hydrogen evolution reaction (HER) at the cathode and oxygen evolution reaction (OER) at the anode of electrolyzers, although the maintenance of long-term performance poses a bigger challenge. To shift the focus of research to the issue of catalyst stability, this review describes the mechanism of HER/OER catalyst degradation based on catalyst dissolution and agglomeration, and summarizes representative catalyst designs for achieving stable catalysts in long-term water electrolysis operation. Additionally, various strategies toward the improvement of HER/OER stability are evaluated, and potential effective guidelines for the design of stable catalysts are suggested.