摘要
Electronic tuning by para substitutions was explored to achieve a highly active manganese N-heterocyclic carbene pincer complex for the selective electrocatalytic reduction of CO_(2)to CO.[MnCNC^(OMe)]BF_(4)(L2-Mn)bearing an electron-donating group(-OMe)showed high activity with 63×catalytic current enhancement,average Faradaic efficiency of 104%,and a TOF_(max) value of 26,127 s^(-1),which is 127 times higher than that of unsubstituted[MnCNCH]Br(L1-Mn)reported previously.In contrast,the electron-withdrawing group(-COOMe)in[MnCNC^(CO^(OMe))]PF_(6)(L3-Mn)inhibited the electrocatalytic activity.Ambient Brønstic acid,however,suppressed the activity of L2-Mn probably due to the protonation of the-OMe group.These findings indicate a potential electronic tuning strategy to improved manganese N-heterocyclic carbene catalysts for CO_(2)reduction.
基金
supported by the National Natural Science Foundation of China(No.21973113)
the Guangdong Natural Science Funds for Distinguished Young Scholar(No.2015A030306027)
the Fundamental Research Funds for the Central Universities。
