Abstract Building up efficient water electrolysis system relays on the development of highly active, cost-effective, and stable electrocatalysts. Carbon-based metal-free catalysts are one of the promising candidates for this purpose. Herein, we report a facile strategy to synthesize nitrogen doped vertical graphene (N-VG) array for catalyzing hydrogen evolution reaction (HER) in acidic electrolyte. The resultant N-VG metal-free catalyst exhibits enhanced HER performance with an overpotential of 290 mV at 10 mA cm−2 and good cycling stability. The enhanced performance is due to the enlarged surface area and optimization of electronic structure induced by the introduction of N heteroatom. Moreover, two possible enhancement mechanisms of N-VG are revealed with first-principle calculations. Our work further demonstrates the effectiveness of N doping on enhancement of HER.

中文翻译：

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氮掺杂垂直石墨烯作为析氢反应的无金属电催化剂

摘要 建立高效的水电解系统依赖于开发高活性、低成本和稳定的电催化剂。碳基无金属催化剂是用于此目的的有希望的候选者之一。在此，我们报告了一种合成氮掺杂垂直石墨烯 (N-VG) 阵列的简便策略，用于在酸性电解质中催化析氢反应 (HER)。所得的 N-VG 无金属催化剂表现出增强的 HER 性能，在 10 mA cm-2 下的过电位为 290 mV，并具有良好的循环稳定性。性能的提高是由于引入 N 杂原子导致表面积扩大和电子结构优化。此外，通过第一性原理计算揭示了 N-VG 的两种可能的增强机制。