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

• Published in: Journal of rare earths Vol. 41; no. 2; pp. 208 - 214
• Main Authors: Zhao, Xiaojie, Chang, Ying, He, Xiaolong, Zhang, Huiqi, Jia, Jingchun, Jia, Meilin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2023
• Subjects: Clusters; Hydrogen evolution reactions; Oxygen evolution reactions; Oxygen vacancies; Rare earths; Clusters; Oxygen vacancies; Hydrogen evolution reactions; Rare earths; Oxygen evolution reactions
• ISSN: 1002-0721; 2509-4963
• DOI: 10.1016/j.jre.2022.01.013

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. A reliable strategy was developed to fabricate IrxCeOx nanocrystals with XC-72R as support by polyol reduction method. The support not only contributes to disperse and regular the nanoclusters, but also greatly promotes the catalysis and improves the overall performance by interacting with the nanoclusters. The addition of Ce3+ ions with macroion radius can cause defects in the layer and promote the formation of oxygen vacancies, which can expose more active sites and enhance the catalytic activity. The feasibility of the development of IrxCeOx clusters provides a new mentality for further development of efficient electrocatalysts for water splitting. [Display omitted]