Gu, Zhengxin; Dou, Zhenlan; Chen, Yuqiu; Zhu, Yanping; Chen, Yubin; Wang, Guoliang; Zou, Zhiqing; Cheng, Qingqing; Yang, Hui

JOURNAL OF POWER SOURCES

2025, ,

Gu, Zhengxin; Dou, Zhenlan; Chen, Yuqiu; Zhu, Yanping; Chen, Yubin; Wang, Guoliang; Zou, Zhiqing; Cheng, Qingqing; Yang, Hui

The urgent need to reduce iridium (Ir) usage in proton exchange membrane water electrolysis (PEMWE) drives the development of highly active and durable Ir-based electrocatalysts for the anodic oxygen evolution reaction (OER). Herein, we propose a strong metal oxide-support interaction (SOSI) interface through synthesizing the Ce doped Nb2O5 supporting ultrasmall IrOx/Ir nanoparticles (IrOx@Ir/Ce-Nb2O5) catalyst. Advanced spectroscopies demonstrate that the Ce-Nb2O5 support lowers the Ir-O coordination number and enriches the electron density at Ir sites. Density functional theory (DFT) calculations reveal that IrOx@Ir/Ce-Nb2O5 shifts the d-band center away from the Fermi level and reduces the energy barrier associated with the rate-determining & lowast;OOH desorption step. Benefiting from above merits, the IrOx@Ir/Ce-Nb2O5 catalyst exhibits a low overpotential of 275 mV at the current density of 10 mA cm(-2) in 0.5 M H2SO4. Impressively, a PEMWE utilizing IrOx@Ir/Ce-Nb2O5 as the anodic catalyst shows the cell voltage of 1.67 V@1.0 A cm(-2) and satisfactory stability (>200 h, 54.71 mu V h(-1)) while reducing the Ir usage as low as 0.3 mg cm(-2).