Understanding ultra-dispersed CeO modified iridium clusters as bifunction electrocatalyst for high-efficiency water splitting in acid electrolytes

Designing bifunctional catalysts with high catalytic activity and durability for electrochemical water splitting has become a promising approach to producing clean and sustainable hydrogen fuels. With high specific surface area and ultra-small size, metal clusters have become a kind of promising catalysts. By introducing Ce species, the noble metal iridium (Ir) can be electronically modulated, thus reduce the activation energy of intermediate, and improve the intrinsic catalytic activity for practical application. The performance of Ir3CeOx/C is more prominent among different feeding ratios of the precursor. The overpotential is only 299 mV for the oxygen evolution reaction (OER), and the overpotential is only 23 mV for the hydrogen evolution reaction (HER) at 10 mA/cm2 in acid media. The Ir doped with appropriate amount of Ce can obtain excellent OER and HER performance and catalyze water splitting efficiently. This work provides a strategic approach to the formation of clusters of precious metals and rare earths.