Promoting selective electroreduction of nitrates to ammonia over electron-deficient Co modulated by rectifying Schottky contacts  

作　　者：Yu Yu Changhong Wang Yifu Yu Yuting Wang Bin Zhang 

机构地区：[1]Department of Chemistry,Institute of Molecular Plus,School of Science,Tianjin University,Tianjin 300072,China [2]Tianjin Key Laboratory of Molecular Optoelectronic Sciences,Collaborative Innovation Center of Chemical Science and Engineering,Tianjin 300072,China

出　　处：《Science China Chemistry》2020年第10期1469-1476,共8页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China(21871206,21701122)。

摘　　要：Developing efficient electrocatalysts for selective nitrate contamination reduction into value-added ammonia is significant.Here,heterostructured Co/CoO nanosheet arrays(Co/CoO NSAs)exhibited excellent Faradaic efficiency(93.8%)and selectivity(91.2%)for nitrate electroreduction to ammonia,greatly outperforming Co NSAs.15N isotope labeling experiments and 1H nuclear magnetic resonance(NMR)quantitative testing methods confirmed the origin of the produced ammonia.Electrochemical in situ Fourier transform infrared(FTIR)spectroscopy,online differential electrochemical mass spectrometry(DEMS)data and density functional theory(DFT)results revealed that the superior performances arose from the electron deficiency of Co induced by the rectifying Schottky contact in the Co/CoO heterostructures.The electron transfer from Co to CoO at the interface could not only suppress the competitive hydrogen evolution reaction,but also increase energy barriers for by-products,thus leading to high Faradaic efficiency and selectivity of ammonia.

关 键 词：ammonia synthesis nitrate reduction electron deficient Co Schottky rectifying effect high selectivity 

分 类 号：TQ426[化学工程] TQ113.26