Excessive nitrate in industrial wastewater is still an important environmental protection issue for human beings. As nitrate promoter metal, Sn has been extensively studied in nitrate reduction reaction (NITRR). However, it suffers from high selectivity of nitrite as the final product at times. As the same main group as Sn, bismuth-based materials have exhibited excellent performance in the field of electrochemical reduction reactions but were rarely investigated for NITRR. In this study, Bi₂O₃ nanosheets in-situ decorated on carbon cloth (Bi₂O₃-CC) was synthesized and it showed larger surface area and higher electrical conductivity than those of dropped Bi₂O₃ nanosheets onto carbon cloth (Bi₂O₃/CC). Experimental results show that the nitrate removal efficiency of Bi₂O₃-CC increased by 12.7% than that of Bi₂O₃/CC at the same condition. Besides, the presence of Cl⁻ benefits the NITRR process since the reaction of Bi₂O₃ and Cl⁻ in acidic conditions can accelerate the conversion of Bi³⁺ to Bi⁰. The mechanism of the NITRR process was proposed based on the electrochemical and scavenging experiments. It was found that both the direct electron transfer and atomic H∗ contribute to the electrochemical reduction of nitrate to ammonia. More importantly, when Bi₂O₃-CC was applied to actual garbage fly ash wastewater, most nitrates were converted to ammonia. The designed Bi₂O₃-CC is a high-potential material for converting nitrate in industrial wastewater to valuable feedstock chemical ammonia with high efficiency.

工业废水中过量的硝酸盐仍然是人类重要的环境保护问题。作为硝酸盐促进剂金属，在硝酸盐还原反应（NITRR）中已经对Sn进行了广泛的研究。然而，它有时遭受作为最终产物的亚硝酸盐的高选择性。作为与Sn相同的主要基团，铋基材料在电化学还原反应领域中表现出出色的性能，但很少对NITRR进行研究。本研究合成了在碳布上原位装饰的Bi ₂ O ₃纳米片（Bi ₂ O ₃ -CC），其比滴落的Bi ₂ O ₃具有更大的表面积和更高的电导率。纳米片到碳布（Bi ₂ O ₃ / CC）上。实验结果表明，Bi的硝酸盐去除效率₂ ö ₃ -CC增加12.7％比的Bi ₂ ö ₃在相同条件下/ CC。此外，氯的存在^-利于NITRR过程，因为Bi的反应₂ ö ₃和Cl ^-在酸性条件下能加速Bi的转换³⁺到碧⁰。基于电化学和清除实验，提出了NITRR过程的机理。发现直接电子转移和原子H *都有助于硝酸盐电化学还原成氨。更重要的是，将Bi ₂ O ₃ -CC用于实际的垃圾飞灰废水时，大多数硝酸盐都转化为氨。设计的Bi ₂ O ₃ -CC是一种高潜力材料，可高效地将工业废水中的硝酸盐转化为有价值的原料化学氨。