Abstract Metal doping for active sites exhibits remarkable potential for improving the hydrogen evolution reaction (HER). Multi-doping and the use of a conductive substrate can further modulate catalytic performance. Herein, Nb-CoSe well dispersed in N-doped carbon nanospheres (NCs, Nb-CoSe@NC) was synthesized to serve as a conductive substrate and facilitated good dispersion of active sites for the HER. Nb doping can also change the electronic structure of CoSe, which facilitates the activity for the HER. In order to further improve the conductivity and intrinsic activity of Nb-CoSe@NC, dual, nonmetal doping was realized through gas sulfurization to prepare hierarchical Nb-CoSeS@NC. The prepared Nb-CoSeS@NC, with a core-shell structure, exhibited a low overpotential of 115 mV at 10 mA cm–2, which is smaller than that of the most doped catalysts. In addition, NCs not only improved the dispersion and conductivity of the catalyst but also prevented metal corrosion in an electrolyte, thus facilitating the long-term stability of Nb-CoSeS@NC. Moreover, the synergistic effect of the multi-doping of Nb, S, and Se was explained. This work provides a promising, multi-doping strategy for the large-scale application of transition-metal-based electrocatalysts for the HER.

中文翻译：

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Nb掺杂辅助的分层CoSeS纳米结构增强析氢反应

摘要 活性位点的金属掺杂在改善析氢反应 (HER) 方面具有显着的潜力。多掺杂和导电基材的使用可以进一步调节催化性能。在此，合成了良好分散在 N 掺杂的碳纳米球（NCs，Nb-CoSe@NC）中的 Nb-CoSe 作为导电基材，并促进了 HER 活性位点的良好分散。Nb 掺杂还可以改变 CoSe 的电子结构，从而促进 HER 的活性。为了进一步提高 Nb-CoSe@NC 的电导率和本征活性，通过气体硫化实现双非金属掺杂制备分级 Nb-CoSeS@NC。制备的 Nb-CoSeS@NC 具有核壳结构，在 10 mA cm-2 下表现出 115 mV 的低过电位，低于大多数掺杂催化剂的过电位。此外，NCs不仅提高了催化剂的分散性和导电性，还防止了电解质中的金属腐蚀，从而促进了Nb-CoSeS@NC的长期稳定性。此外，还解释了 Nb、S 和 Se 多掺杂的协同效应。这项工作为过渡金属基电催化剂在 HER 中的大规模应用提供了一种有前景的多掺杂策略。