【摘要】 氨是化肥生产和化学工业的重要原料,也是良好的无碳储能燃料.相比于工业应用上能耗大、转化率低的哈勃博施(Haber-Bosch)法,电催化合成氨的方法能够在温和条件下绿色高效地合成氨.本文综合评述了以氮气、硝酸根和一氧化氮作为不同氮源时电催化合成氨的反应机理,并结合不同氮源的特点分析了各自的研究进展与优势,分别讨论了氮气难以溶解在水中被吸附和活化、硝酸盐还原元素价态跨度大难以控制中间体和反应路径及一氧化氮体系复杂、水溶液中析氢副反应难以控制等问题,总结了运用不同策略开发高活性、高稳定性催化剂以提高反应效率和选择性、优化反应装置以减小传质影响、选用不同电解质体系改善反应过程等解决思路.最后,对不同氮源电催化合成氨的未来发展趋势和应用前景进行了展望.更多还原

【Abstract】 Ammonia is an important raw material for fertilizer production and chemical industry, and is also a good carbon-free energy storage fuel. Compared with the Haber-Bosch method for industrial-scale ammonia synthesis with high energy consumption and low conversion rate, the electrocatalytic ammonia synthesis method has the advantages of green and high efficiency under mild environmental conditions. This article reviews the reaction mechanism of electrocatalytic ammonia synthesis when using nitrogen, nitrate, and nitrogen oxide as different nitrogen sources.Based on the characteristics of different nitrogen sources, the research progress and advantages of each are analyzed.The problems of difficulty in controlling intermediates and reaction paths for nitrate reduction because of the large elemental valence span, complexity of the nitrogen oxide system, difficulty in controlling the hydrogen evolution reaction, and difficulty in dissolving nitrogen in water for activation are discussed, respectively. The solutions are summarized to develop high activity catalysts with different strategies to improve the reaction efficiency and selectivity, to optimize the reaction device to reduce the influence of mass transfer, and to select different electrolyte systems to improve the reaction process.更多还原