We studied electrochemical nitrogen reduction reactions (NRR) to ammonia on single atom catalysts (SACs) anchored on defective graphene derivatives by density functional calculations. We find significantly improved NRR selectivity on SACs compared to that on the existing bulk metal surface due to the great suppression of the hydrogen evolution reaction (HER) on SACs with the help of the ensemble effect. In addition, several SACs, including [email protected]₄ (0.69 eV) and [email protected]₄ (0.87 eV), are shown to exhibit lower free energy for NRR than that of the Ru(0001) stepped surface (0.98 eV) due to a strong back-bonding between the hybridized d-orbital metal atom in SAC and π* orbital in *N₂. Formation energies as a function of nitrogen chemical potential suggest that [email protected]₄ and [email protected]₄ are also synthesizable under experimental conditions.

中文翻译：

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用单原子催化剂抑制电化学还原N _2中的氢生成反应：计算指南

我们通过密度泛函计算研究了锚定在有缺陷的石墨烯衍生物上的单原子催化剂（SAC）上对氨的电化学氮还原反应（NRR）。我们发现与现有的块状金属表面相比，SAC的NRR选择性显着提高，这是由于借助集合效应极大地抑制了SAC上的析氢反应（HER）。此外，还显示了几种SAC，包括[受电子邮件保护] ₄（0.69 eV）和[受电子邮件保护] ₄（0.87 eV），其NRR的自由能比Ru（0001）台阶表面（0.98 eV）的自由能低。由于SAC中杂化的d轨道金属原子与* N _2中的π*轨道之间有很强的反向键合。作为氮化学势的函数的形成能表明，在实验条件下也可以合成[受电子邮件保护的] ₄和[受电子邮件保护的] ₄。