Nitrogen fixation under ambient conditions remains a significant challenge. Here, we report nitrogen fixation by Ru single-atom electrocatalytic reduction at room temperature and pressure. In contrast to Ru nanoparticles, single Ru sites supported on N-doped porous carbon greatly promoted electroreduction of aqueous N₂ selectively to NH₃, affording an NH₃ formation rate of 3.665 $\mathrm{m}{\mathrm{g}}_{\mathrm{N}{\mathrm{H}}_{\mathrm{3}}}{\mathrm{h}}^{-\mathrm{1}}\mathrm{m}{\mathrm{g}}_{\mathrm{Ru}}^{-\mathrm{1}}$ at −0.21 V versus the reversible hydrogen electrode. Importantly, the addition of ZrO₂ was found to significantly suppress the competitive hydrogen evolution reaction. An NH₃ faradic efficiency of about 21% was achieved at a low overpotential (0.17 V), surpassing many other reported catalysts. Experiments combined with density functional theory calculations showed that the Ru sites with oxygen vacancies were major active centers that permitted stabilization of *NNH, destabilization of *H, and enhanced N₂ adsorption. We envision that optimization of ZrO₂ loading could further facilitate electroreduction of N₂ at both high NH₃ synthesis rate and faradic efficiency.

在环境条件下固氮仍然是一项重大挑战。在这里，我们报告在室温和压力下通过Ru单原子电催化还原进行固氮。与Ru纳米颗粒相比，负载在N掺杂的多孔碳上的单个Ru位置极大地促进了N ₂选择性地电还原为NH ₃，从而使NH _3的形成速率为3.665$\mathrm{米}{\mathrm{G}}_{\mathrm{ñ}{\mathrm{H}}_{\mathrm{3}}}{\mathrm{H}}^{-\mathrm{1个}}\mathrm{米}{\mathrm{G}}_{\mathrm{茹}}^{-\mathrm{1个}}$相对于可逆氢电极为-0.21V。重要的是，发现添加ZrO ₂可以显着抑制竞争性的析氢反应。在低过电势（0.17 V）时，NH ₃法拉第效率达到了约21％，超过了许多其他报道的催化剂。与密度泛函理论计算相结合的实验表明，具有氧空位的Ru位是主要的活性中心，可以使* NNH稳定，* H不稳定和增强N ₂吸附。我们预见到ZrO ₂负载的优化可以进一步促进N ₂在高NH ₃合成速率和法拉第效率下的电还原。