摘要
氨(NH_(3))是现代工业的重要化工原料之一,因其具有较高的能量密度、便于运输和储存的特点而被认为是一种非常有前景的储氢材料和可再生能源载体.电催化硝酸根还原(NO_(3)RR)是一种理想的绿色合成氨策略,同时可应用于废水中硝酸根(NO_(3)−)污染的去除.然而,NO_(3)RR涉及多个电子和质子转移过程,且存在析氢反应(HER)等竞争反应,导致NO_(3)RR的法拉第效率(FE)和选择性较低.近年来,精准构筑NO_(3)RR电催化剂,实现高效合成氨逐步成为电催化领域的研究热点.其中,铁/铜基催化剂因其优异的催化性能和经济可行性而备受关注.因此,对近年来具有代表性的铁/铜基催化剂的研究进展进行总结是非常必要的.本文首先简述了电化学NO_(3)RR合成氨可能发生的反应路径,主要围绕铁/铜基电催化剂在NO_(3)RR中可能涉及的反应历程和相应的中间体.在此基础上,针对不同的反应机理系统归纳了三种催化剂设计策略,包括单原子催化剂策略、双金属催化剂策略以及仿生催化剂策略等.随后,重点评析和讨论了原位实时表征技术,如原位电化学质谱、原位X射线吸收光谱和原位红外/拉曼等,在电催化NO_(3)RR合成氨研究领域中的代表性应用案例,并阐明了原位表征技术的发展和联用对于揭示NO_(3)RR本征活性位和动态机理的关键作用.最后,系统总结了当前NO_(3)RR所面临的核心挑战并对其未来的研究机遇和发展方向进行了展望,包括高效催化剂的关键描述符和设计策略,探究固-液界面的前沿原位表征技术开发,以及将NO_(3)RR与绿色反应(如二氧化碳转化和生物质转化等)高效耦联制备高值化学品.综上所述,尽管电催化NO_(3)RR合成氨目前仍面临诸多挑战,随着实验方案、科学理论和原位表征技术的不断发展,未来将会出现更多高效且稳定的NO_(3)RR催化剂.本文旨在为高效电催化剂的理性开发,深入理解其动态反应机理与催化剂构效关系提供参考.
Electrocatalytic reduction reaction of nitrate(NO_(3)RR)to ammonia is becoming ever more pivotal for the sustainable production of NH_(3),alleviating the nitrate pollution and even for rebalancing the nitrogen cycle globally.Considerable efforts have been devoted to the rational development of catalyst systems in electrocatalytic NO_(3)RR to NH_(3),and Fe/Cu-containing catalysts have shown significant advantages and are currently in the spotlight which have addressed remarkable attention and academic interest.In this Perspective,we first briefly discuss the possible reaction pathways of electrocatalytic NO_(3)RR to NH_(3).Emphasis is put on the three catalyst approaches for enhancing the NO_(3)RR performance,based on the selected case studies of the most representative Fe/Cu-containing catalysts.Furthermore,this Perspective assesses the recent progress on the utility and application of the state-of-the-art in situ characterization technologies applied in recent showcases of electrocatalytic NO_(3)RR to NH_(3),with a special focus on spectroscopies.Finally,the open challenges and outlook regarding the rational design of efficient electrocatalysts,the development of correlative in situ characterization technologies and the further coupling promising reactions for production of value-added products are examined for inspiring the future work.
作者
陈丽丽
郝彦衡
褚健意
刘松
白凤华
罗文豪
Lili Chen;Yanheng Hao;Jianyi Chu;Song Liu;Fenghua Bai;Wenhao Luo(Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials,College of Chemistry and Chemical Engineering,Inner Mongolia University,Hohhot 010021,Inner Mongolia,China;Chemical Engineering and Resource Utilization,College of Chemistry,Northeast Forestry University,Harbin 150040,Heilongjiang,China)
基金
国家自然科学基金(22078316)
内蒙古大学骏马计划资助(10000-23112101/081)
内蒙古青年科技人才资助(NJYT24019).
关键词
电催化
硝酸根还原
合成氨
铁/铜基催化剂
原位表征
Electrocatalysis
Nitrate reduction reaction
Ammonia synthesis
Fe/Cu-containing catalyst
In situ characterization
