Advanced Transition Metal‐Based OER Electrocatalysts: Current Status, Opportunities, and Challenges

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 17; no. 37; pp. e2100129 - n/a
• Main Authors: Zhang, Kexin, Zou, Ruqiang
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01-09-2021
• Subjects: Adsorbates; Catalysts; electrocatalysis; Electrocatalysts; Electron transfer; Energy storage; Metal air batteries; Nanotechnology; Optimization; oxygen evolution; Oxygen evolution reactions; Performance enhancement; Principles; Rechargeable batteries; transition metal; Transition metals; Water splitting
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202100129

Oxygen evolution reaction (OER) is an important half‐reaction involved in many electrochemical applications, such as water splitting and rechargeable metal–air batteries. However, the sluggish kinetics of its four‐electron transfer process becomes a bottleneck to the performance enhancement. Thus, rational design of electrocatalysts for OER based on thorough understanding of mechanisms and structure‐activity relationship is of vital significance. This review begins with the introduction of OER mechanisms which include conventional adsorbate evolution mechanism and lattice‐oxygen‐mediated mechanism. The reaction pathways and related intermediates are discussed in detail, and several descriptors which greatly assist in catalyst screen and optimization are summarized. Some important parameters suggested as measurement criteria for OER are also mentioned and discussed. Then, recent developments and breakthroughs in experimental achievements on transition metal‐based OER electrocatalysts are reviewed to reveal the novel design principles. Finally, some perspectives and future directions are proposed for further catalytic performance enhancement and deeper understanding of catalyst design. It is believed that iterative improvements based on the understanding of mechanisms and fundamental design principles are essential to realize the applications of efficient transition metal‐based OER electrocatalysts for electrochemical energy storage and conversion technologies.
Recent achievements on transition‐metal based electrocatalysts for oxygen evolution reaction electrocatalysts are comprehensively overviewed. Specifically, two different mechanisms, several descriptors, and fundamental concepts in catalysis are first discussed. Various strategies and representative studies are then provided to reveal the novel design principles before finally offering perspectives on some potential research directions for further catalytic performance enhancement and deeper understanding of catalyst design.