Nitrate pollution is a critical environmental issue in need of urgent addressing. Electrochemical reduction is an attractive strategy for treating nitrate due to the environmental friendliness. However, it is still a challenge to achieve the simultaneous high activity and selectivity. Here we report the design of a porous tubular carbon membrane as the electrode deposited with catalysts, which provides a large triple-phase boundary area for nitrate removal reactions. The achieved nitrate removal rate is one order of magnitude higher than other literatures with high nitrate conversion and high selectivity of nitrogen. The carbon membrane itself had a limited catalytic property thus Cu-Pd bimetal catalysts were deposited inside the nano-pores to enhance the activity and selectivity. When Na₂SO₄ electrolyte was applied, the achieved single-pass removal of nitrate was increased from 55.15% (for blank membrane) to 97.12% by adding catalysts inside the membrane. In case of NaOH as the electrolyte, the single-pass nitrate removal efficiency, selectivity to nitrogen formation and nitrate removal rate was 90.66%, 96.40% and 1.47 × 10⁻³ mmol min⁻¹ cm⁻², respectively. Density functional theory studies demonstrate that the loading of bimetal catalysts compared with single metal catalysts enhances the adsorption of *NO₃ on membrane surface favorable for N₂ formation than NH₃ on Cu-Pd surface. The application of catalytic carbon membrane nano-reactors can open new windows for nitrate removal due to the high reactor efficiency.

硝酸盐污染是一个亟待解决的严重环境问题。由于环境友好，电化学还原是处理硝酸盐的有吸引力的策略。然而，同时实现高活性和选择性仍然是一个挑战。在这里，我们报告了多孔管状碳膜的设计，作为沉积有催化剂的电极，它为硝酸盐去除反应提供了一个大的三相边界区域。达到的硝酸盐去除率比其他具有高硝酸盐转化率和高氮选择性的文献高一个数量级。碳膜本身的催化性能有限，因此将Cu-Pd双金属催化剂沉积在纳米孔内以提高活性和选择性。当 Na ₂ SO ₄使用电解液，通过在膜内添加催化剂，实现的硝酸盐单程去除率从 55.15%（对于空白膜）增加到 97.12%。在NaOH作为电解质的情况下，单程硝酸盐去除效率、氮形成选择性和硝酸盐去除率分别为90.66%、96.40%和1.47×10 ^-3  mmol min ^-1  cm ^-2。密度泛函理论研究表明，与单金属催化剂相比，双金属催化剂的负载增强了*NO ₃在膜表面的吸附，有利于 N _{2 的}形成，而不是 NH ₃在铜钯表面。由于反应器效率高，催化碳膜纳米反应器的应用可以为硝酸盐的去除打开新​​的窗口。