High-Stability RuO₂/MoO₃ Electrocatalyst for the Oxygen Evolution Reaction in Proton-Exchange-Membrane Water Electrolysis

The slow kinetics and low durability of catalysts in the oxygen evolution reaction (OER) have been long-standing issues. The scarcity and high cost of iridium have posed limitations on its widespread implementation. Therefore, a noniridium catalyst with high activity and stability is the key for proton-exchange-membrane water electrolysis. This work reports a high activity and stability RuO 2 /MoO 3 catalyst for water electrolysis. The catalyst exhibits an oxygen evolution reaction (OER) performance with an overpotential of 267 mV at 10 mA cm –2 and demonstrates outstanding long-term stability. Moreover, the PEMWE cell-based RuO 2 /MoO 3 anode achieves an overpotential of 0.777 V at 2 A cm –2 and high stability for 12 h at 1 A cm –2 .