Proton exchange membrane (PEM) water electrolysis is a green and sustainable method of hydrogen production. The development of efficient and economical electrocatalysts for anodic oxygen evolution reaction (OER) is the key to its large-scale commercialization. Iridium oxide catalysts supported by different manganese based oxide carriers (IrOx/Mn8O10Cl3, IrOx/β-MnO2 and IrOx/α-MnO2) were prepared by two-step synthesis method, and the content of iridium is about 55%. Compared with the commercial IrO2 and other noble metal containing electrocatalysts, the synthesized catalysts have lower overpotential and higher current density. The overpotential of IrOx/β-MnO2 is only 228 mV at the current density of 10 mA/cm2. The specific mass activity of IrOx/Mn8O10Cl3 reaches 916.7 A/gIr at 1.53V. The enhancement of OER activity is attributed to the abundant hydroxyl oxygen defects and IrIII species on the catalyst surface. The rich crystalline-amorphous interface provides a large number of active sites for the reaction. The iridium oxide/manganese based oxide catalysts reported in this paper provide new insights for the development of efficient and economical catalysts for acidic OER.
