泡沫镍负载CuO纳米花的构筑及电化学硝酸根还原制氨的性能  

Construction of Nickel Foam Supported CuO Nanoflower Composite and Its

作　　者：黄顺元 刘律飞 顾韵洁 葛帅辰 李静莎 HUANG Shunyuan;LIU Lyufei;GU Yunjie;GE Shuaichen;LI Jingsha(Institute of Materials Science and Devices,Suzhou University of Science and Technology,Suzhou 215009,Jiangsu,China)

机构地区：[1]苏州科技大学材料科学与器件研究院,江苏苏州215009

出　　处：《材料导报》2024年第10期63-69,共7页Materials Reports

基　　金：江苏省自然科学基金青年项目(BK20200991) 。

摘　　要：电化学硝酸根还原制氨(Nitrate reduction to ammonia, NRA)是以硝酸根和水分别作为氮和氢的来源,采用电化学的途径实现室温下氨的绿色合成兼去除水中硝酸盐污染物,对缓解能源危机和环境问题具有重要的研究意义。然而,硝酸根到氨是一个复杂的8e-转移过程且伴随着激烈的析氢副反应,这严重制约了合成氨的选择性和法拉第效率。为此,采用水热合成法及后续的热处理设计制备了泡沫镍负载氧化铜纳米花催化剂并探究其电化学硝酸根还原制氨性能。通过调控硝酸铜与尿素比例、热解温度等合成条件,达到泡沫镍(Ni foam, NF)均匀负载CuO纳米花的目的。结果表明,当Cu(NO3)2、CO(NH2)2的物质的量比为1∶6时,所得到的目标催化剂(CuO-6@NF)在法拉第效率、NH3产率、选择性和硝酸盐转换率方面表现出最佳性能。在-0.23 V vs.RHE情况下,CuO-6@NF NH3的产率达到1.15 mmol·h-1·cm-2,选择性为89.36%,总氮的去除率高达96.71%。此外,该催化剂还表现出良好的再现性、高稳定性以及较宽泛浓度下的适用性。Electrochemical nitrate reduction to ammonia(NRA)could realize the green synthesis of ammonia and remove nitrate pollutant through electrochemical pathways by using nitrate and water as sources of nitrogen and hydrogen,respectively,which is of significance for alleviating energy crisis and environmental problems.However,nitrate to ammonia is a complex eight-electron transfer process accompanied by intense hydrogen evolution side reactions,which seriously limits the selectivity and Faraday efficiency of ammonia synthesis.Therefore,nickel foam-supported copper oxide nanoflower catalyst was prepared by hydrothermal synthesis and subsequent heat treatment process,and its electrocatalytic performance for nitrate reduction to ammonia was explored.By adjusting the synthesis conditions such as the ratio of copper nitrate to urea and pyrolysis temperatures,the uniform CuO nanoflowers loaded on nickel foam(NF)was achieved.The results show that when n(Cu(NO 3)2)∶n(CO(NH 2)2)is 1∶6,the obtained target catalyst(CuO-6@NF)shows the best performance in terms of Faraday efficiency,NH 3 yield,selectivity and nitrate conversion.At-0.23 V vs.RHE,the yield of CuO-6@NF ammonia reached 1.15 mmol·h-1·cm-2,the selectivity was 89.36%,and the removal rate of total nitrogen was as high as 96.71%.In addition,the catalyst exhibits good reproducibility,high stability,and applicability over a wide range of concentrations.

关 键 词：硝酸根还原 合成氨 电催化剂 CuO纳米花 异质结 

分 类 号：TQ151[化学工程—电化学工业]