Multi-functional engineering of rare earth-based catalysts for high-efficiency water splitting
Shisheng Yuan, Yuman Wang, Huanyu Zhao, Zhipeng P. Liu, Zhongyi Liu, Zhuo Guo, Rongguang Li
Abstract
Against the backdrop of global carbon neutrality goals, hydrogen production via electrochemical water splitting has emerged as a promising pathway for sustainable energy conversion. However, the sluggish kinetics of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) necessitate highly efficient electrocatalysts. While noble metal-based catalysts exhibit superior performance, their high cost and scarcity impede large-scale application. Rare earth elements (REEs), with their unique 4f electronic configurations, variable oxidation states, and strong oxygen affinity, offer exceptional potential for modulating the electronic and geometric structures of electrocatalysts. This review comprehensively summarizes recent advances in the application of REEs in electrocatalytic water splitting, with a focus on HER and OER. Key strategies such as doping, defect engineering, alloying, heterostructure construction and other strategies are discussed, highlighting how REEs enhance catalytic activity, stability, and bifunctional performance across acidic, alkaline, and neutral media. Specific attention is given to La-, Ce-, and Er-based catalysts, which demonstrate performance comparable to or surpassing that of noble metal benchmarks. This review summarizes recent progress in rare earth-based electrocatalysis and highlights key challenges such as sustainability, resource utilization, and mechanistic understanding. It emphasizes the role of strategies such as doping, defect, alloy, and heterostructure engineering in optimizing activity and stability. By integrating in situ characterization with data-driven design, it provides guidance for developing next-generation, eco-friendly REE-based catalysts for green hydrogen production.