Recent advances in morphology control of platinum catalysts toward oxygen reduction reaction

Abstract

Exploring advanced platinum (Pt)-based electrocatalysts is vital for the widespread implementation of proton exchange membrane fuel cells (PEMFCs). Morphology control represents an effective strategy to optimize the behavior of Pt catalysts. In this work, an attempt is made to comprehensively review the effect of morphology control on the catalytic behavior of catalysts in the oxygen reduction reaction (ORR). First, the fundamental physicochemical changes behind morphology control, including exposing more active sites, generating appropriate lattice strains, and forming different crystalline surfaces, are highlighted. Then, recently developed strategies for tuning the morphologies of electrocatalysts, including core-shell structures, hollow structures, nanocages, nanowires, and nanosheets, are comprehensively summarized. Finally, an outlook on the future development of morphology control of Pt catalysts is presented, including rational design strategies, advanced in situ characterization techniques, novel artificial intelligence, and mechanical learning. This work is intended to provide valuable insights into designing the morphology and technological innovation of efficient redox electrocatalysts in fuel cells.

Key words： morphology; platinum catalysts; electrocatalysis; ORR; PEMFC

Acknowledgements

This work was supported by the Natural Science Foundation of Shaanxi Province, China (No. 2023-JC-YB-122), the High-level Innovation and Entrepreneurship Talent Project from Qinchuangyuan of Shaanxi Province, China (No. QCYRCXM-2022-226), the Fundamental Research Funds for the Central Universities, China (No. D5000210987), the Joint Fund Project-Enterprise-Shaanxi Coal Joint Fund Project, China (No. 2021JLM-38), the National Natural Science Foundation of China (Grant No. 22379123, No. 22250710676 ), the Fujian Province Minjiang Scholar Program, China.

Competing interests

The authors declare that they have no competing interests.

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