Developing green, sustainable and economical materials for emerging electrochemical remediation of nitrate (NO₃^-) contaminant have attracted immense research interest. In this study, a cost-effective and stable three-dimensional P-doped Co₃O₄/nickel foam (NF) was prepared for electrocatalytic reduction of NO₃^- in water. The doping of P could replace the lattice oxygen in Co₃O₄ and lead to the enhancements in Co³⁺ percentage and empty d orbitals. As a result, the relative energy for Volmer reaction and the adsorption energy of atomic H* decreased to be -0.73 eV and -3.60 eV, respectively. Furthermore, the higher electrochemical active area and lower interface impedance of Co₃O₄ were attained after P doping. The P_2.1-Co₃O₄/NF cathode outperformed Co₃O₄/NF in the NO₃^- reduction rate (8.45 times faster) and contribution of atomic H* (2.37 folds increase in the ratio). And almost 100% N₂ selectivity can be obtained in the presence of 2500 mg L^-1 chloride ions. Generally, this study provided a new paradigm for designing more practical non-metallic catalyst for NO₃^- reduction.

新兴硝酸盐的电化学处理（无显影绿色的，可持续的和经济的材料₃ ^-污染物已引起极大的研究兴趣）。在这项研究中，具有成本效益的和稳定的三维P掺杂钴₃ ö ₄ /镍泡沫（NF）是为NO的电催化还原制备₃ ^-水。P的掺杂可以替代Co ₃ O _4中的晶格氧并导致Co ³⁺的增强百分比和空d轨道。结果，用于Volmer反应的相对能量和原子H *的吸附能分别降低至-0.73eV和-3.60eV。另外，P掺杂后，Co ₃ O ₄具有较高的电化学活性面积和较低的界面阻抗。在P _2.1 -Co ₃ ö ₄ / NF阴极优于联合₃ ö ₄ / NF中的NO ₃ ^-还原率（更快8.45倍）和原子H *的贡献（2.37倍的比例增加）。在2500 mg L ^-1的存在下，几乎可以获得100％的N ₂选择性氯离子。一般地，本研究为设计NO更实用的非金属催化剂提供一个新的范例₃ ^-还原。