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Facile grafting strategy synthesis of single-atom electrocatalyst with enhanced ORR performance

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Abstract

Single-atom catalysts (SACs) have become one of the most considered research directions today, owing to their maximum atom utilization and simple structures, to investigate structure-activity relationships. In the field of non-precious-metal electrocatalysts, atomically dispersed Fe-N4 active sites have been proven to possess the best oxygen reduction activity. Yet the majority of preparation methods remains complex and costly with unsatisfying controllability. Herein, we have designed a surface-grafting strategy to directly synthesize an atomically dispersed Fe-NVC electrocatalyst applied to the oxygen reduction reaction (ORR). Through an esterification process in organic solution, metal-containing precursors were anchored on the surface of carbon substrates. The covalent bonding effect could suppress the formation of aggregated particles during heat treatment. Melamine was further introduced as both a cost-effective nitrogen resource and blocking agent retarding the migration of metal atoms. The optimized catalyst has proven to have abundant atomically dispersed Fe-N4 active sites with enhanced ORR catalytic performance in acid condition. This method has provided new feasible ideas for the synthesis of SACs.

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Acknowledgements

This work was partially supported by National Key R&D Plan of China (No. 2016YFB0101308), the National Natural Science Foundation of China (Nos. 21802069, 21676135, and U1508202), China Postdoctoral Science Foundation (No. 2018M642213), and “333” project of Jiangsu Province (No. BRA2018007).

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Ding, R., Liu, Y., Rui, Z. et al. Facile grafting strategy synthesis of single-atom electrocatalyst with enhanced ORR performance. Nano Res. 13, 1519–1526 (2020). https://doi.org/10.1007/s12274-020-2768-y

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