Corresponding Author

Xue-Ping Qin(xqinaa@connect.ust.hk);
Min-Hua Shao(kemshao@ust.hk)


Single atom catalysts (SAC) have been regarded as the promising alternatives to platinum group metals due to their low costs and potentially high catalytic activities in various electrocatalytic reactions. The atomic mechanism understanding of activity discrepancy among different metal and nitrogen co-doped carbon-based catalysts is still lacking. Here, non-precious metal and nitrogen co-doped carbons (Me-N-C, Me = Fe and Co) as the model catalysts are investigated by combining experimental and theoretical studies to explore the catalytic activities and corresponding reaction mechanisms toward oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) at universal pHs. Atomic theoretical simulations suggest that Fe-N-C has higher ORR activity than Co-N-C due to its lower reaction barrier of the rate-determining step, while the activity trend is reversed for HER. Our simulation results are consistent with experimental observations.

Graphical Abstract


oxygen reduction reaction, hydrogen evolution reaction, electrocatalysts, single atom catalysts, theoretical calculations

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