Corresponding Author

Jian-Bing Zhu(zjb@ciac.ac.cn);
Wei Xing(zmzhang@jlu.edu.cn)


Oxygen reduction reaction (ORR) in alkaline electrolytes is an important electrochemical process for metal-air batteries and anion exchange membrane fuel cells (AEMFCs). However, the sluggish kinetics spurs intensive research on searching robust electrocatalysts. Non-precious metal catalysts (NPMCs) that can circumvent the cost and scarcity issues associated with platinum (Pt)-based materials have been pursued and the challenges lie in the performance improvement to rival Pt-based benchmarks. As the composition and structure of the NPMCs have a significant impact on the catalytic performance, precise regulation on the catalyst structure holds great promise to bridge the activity gap between NPMCs and Pt-based benchmarks. In this minireview, we aim to provide an overview of recent progress in the structural regulation on NPMCs towards improved performance. The four typical categories of NPMCs, i.e., metal-free carbon-based materials, metal compounds, metal encapsulated in graphitic layer and atomically dispersed metal-nitrogen-carbon materials, are firstly introduced, where catalytic active sites and catalytic mechanism are highlighted. Subsequently, we summarize the representative structural regulation from a nanoscale to an atomic scale including hierarchically porous structure regulation, interface engineering, defect engineering and atomic pair construction. Special emphasis is placed on the elucidation of the catalytic structure-performance relationship. The origins of activity improvements from these structural regulations are discussed in terms of accelerated mass transfer, increased accessible active sites, tailored electronic states, and synergetic effect between multi-components. Finally, the challenges and opportunities are discussed.

Graphical Abstract


oxygen reduction reaction, non-precious metal catalysts, structural regulation

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