Environmentally friendly electrochemical reduction pathways from NO₃⁻ to NH₃ or N₂ have provided feasible strategy into the green production of ammonia or the treatment of nitrate wastewater. Here, we anchored single-atom Cu with boron carbon nitride on carbon nanotube (BCN@Cu/CNT), and achieved the efficient operation of electrochemical nitrate reduction reaction (NIRR). BCN@Cu/CNT can efficiently catalyze the selective conversion of high-concentration nitrate into high-value-added ammonia, where the ammonia yield rate and Faradaic efficiency are as high as 172,226.5 μg h⁻¹ mg_cat.⁻¹ and 95.32% (at −0.6 V), respectively. BCN@Cu/CNT also shows the ability to efficiently remove low-concentration nitrates in sewage. Specifically, here only takes 5 h to nearly 100% (99.32%) eliminate NO₃^- (50 mg L⁻¹) in sewage without any residual NO₂⁻. The excellent catalytic activity and physicochemical stability of BCN@Cu/CNT for NIRR suggest the promising industrial application prospects, including the green production of ammonia and the purification of nitrate wastewater.

_{从NO 3} ^-到NH ₃或N ₂的环保电化学还原途径为氨的绿色生产或硝酸盐废水的处理提供了可行的策略。在这里，我们将单原子Cu与氮化碳硼锚定在碳纳米管上（BCN@Cu/CNT），实现了电化学硝酸盐还原反应（NIRR）的高效运行。BCN@Cu/CNT可以高效催化高浓度硝酸盐选择性转化为高附加值氨，氨收率和法拉第效率高达172,226.5 μg h ^-1 mg _cat。^-1和 95.32%（在 -0.6 V 时）。BCN@Cu/CNT 还显示出有效去除污水中低浓度硝酸盐的能力。具体来说，这里只需要5小时就几乎100%（99.32%）消除了污水中的NO ₃ ^-（50 mg L ^-1），没有任何残留的NO ₂ ^-。BCN@Cu/CNT对NIRR具有优异的催化活性和物理化学稳定性，在氨的绿色生产和硝酸盐废水的净化等方面具有广阔的工业应用前景。