LAUSR

Herein, the low cost and efficient oxygen‐deficient Ti0.9Nb0.1O2‐x as support of IrO2 (noted as IrO2/TNO) anode catalyst for the PEM water electrolyzer is synthesized and then characterized using a series of techniques. Oxygen vacancies are introduced by hydrogenation treatment. The IrO2/TNO sample after hydrogenation (noted as IrO2/TNO−Hx, x corresponds to the hydrogenation temperature) exhibits enhanced electronic conductivity and increased surface active sites relative to that of the pristine IrO2/TNO sample. A single cell is assembled by IrO2/TNO−Hx as anode catalyst, commercial Pt/C as cathode catalytic and Nafion 117 membrane as electrolyte. At a low loading mass of IrO2, the IrO2/TNO−H750 sample shows the optimum oxygen evolution reaction (OER) activity (1.832 V at 1 A ⋅ cm−2), which is superior to that of unsupported IrO2 (1.858 eV at 1 A ⋅ cm−2), and remains stable for 100 h operating at a current density of 1 A cm−2. This work provides a rational design strategy for developing low cost and efficient anode catalysts support.