Recent advances and trends of single-atom catalysts for proton exchange membrane fuel cell cathodes

Abstract

Proton exchange membrane fuel cells (PEMFCs), which have the advantages of high-power density, zero emission, and low noise, are considered ideal electrochemical conversion systems for converting hydrogen (H₂) and oxygen (O₂)/air into electricity. However, the oxygen reduction reaction (ORR), which is accompanied by multiple electrons, results in voltage loss and low conversion efficiency of PEMFCs. Currently, PEMFCs mainly use high-load precious platinum (Pt) to promote the ORR process; however, the high cost of Pt hinders the widespread commercialization of PEMFCs. Over the past few years, metal-nitrogen-carbon single-atom catalysts (M-N-C SACs) have attracted considerable attention and have been recognized as potential Pt-based catalysts owing to their outstanding ORR activity. This review briefly introduces the components of PEMFCs. Second, we discuss the catalytic mechanisms of the M-N-C SACs for the ORR. Third, the latest advances in noble, non-noble, and heteroatom-doped M-N-C SACs used as ORR and PEMFCs cathode catalysts are systematically reviewed. In summary, we have outlined the current challenges and proposed a future perspective of M-N-C SACs for PEMFCs cathodes.

Keywords

Proton exchange membrane fuel cells / Oxygen reduction reaction Cathode / Platinum-based catalysts / Metal-nitrogen-carbon single-atom catalysts

Declaration of Competing Interest

Zhonghua Zhang is an editorial board member for ChemPhysMater and was not involved in the editorial review or the decision to publish this article. The authors declare the following personal relationships which may be considered as competing interests: Feng Liu is currently employed by Datong Innoreagen Power Technology Co., Ltd. Other authors declare that there are no competing interests.

CRediT authorship contribution statement

Zihao Wan: Writing - review & editing, Writing - original draft, Investigation, Conceptualization. Feng Liu: Writing - review & editing, Resources, Investigation. Hongfei Xu: Writing - review & editing, Resources, Investigation. Shuaili Zhao: Writing - review & editing, Resources, Investigation. Zhen An: Writing - review & editing, Resources, Investigation. Zizai Ma: Writing - review & editing, Supervision. Zhonghua Zhang: Writing - review & editing, Supervision. Yun Wu: Investigation, Resources, Writing - review & editing. Xiaoguang Wang: Writing - review & editing, Supervision.

Acknowledgements

The authors gratefully acknowledge the National Natural Science Foundation of China (22008165 and 21878201), Natural Science Foun-dation of Shanxi Province (202303021211035 and 202203021212240), and the 7th Youth Talent Support Program of Shanxi Province.

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