Incorporation of rare earth elements with transition metal-based materials for electrocatalysis: a review for recent progress

Improving the catalytic activity of various electrocatalysts is of significant importance for the efficient conversion between electricity and chemical energy for sustainable developments. Lately, modification of transition metal-based electrocatalysts with foreign elements is growing rapidly, and rare earth (RE) elements are of particular interest among various elements because of their special structural features. Here, in this review, we perform a comprehensive survey on the recent progress in RE element -incorporated electrocatalysts for various electrochemical reactions, including hydrogen evolution, oxygen evolution, oxygen reduction, and methanol oxidation reactions. As benefited from the RE incorporation, the structural and catalytic property changes of host electrocatalysts are summarized for different reactions, in which it is evident that there are many positive promotions induced from RE elements for the enhanced electrocatalysis. Several important insights are also discussed to further our knowledge of integrating RE elements to improve associated electrocatalytic properties of the catalysts investigated. The final section describes the challenges for the design, structural optimization, mechanistic investigation, and technological applications for the RE element-incorporated electrocatalysts and concludes with an outlook on the future development of these catalysts for energy conversion and storage. (C) 2019 Elsevier Ltd. All rights reserved.