作者自行合成了离子液体[BMIM]BF4,用循环伏安法(CV)、计时电量法(CA)和电化学原位红外反射光谱(in situFTIR),从分子水平考察了离子液体中马来酸在玻碳(GC)电极上的电化学还原过程。结果表明,[BMIM]BF4中马来酸在GC电极上的还原为不可逆过程,测得扩散系数D=9.62×10-8cm2/s;in situFTIRS研究发现,马来酸在离子液体[BMIM]BF4和水溶液中的电还原生成丁二酸的机理不同。在[BMIM]BF4中马来酸还原发生在其中的一个羧基上,即马来酸首先获得一个电子生成阴离子自由基,随后可能获得一个电子生成二价阴离子,或者获得一个电子并在2个H+的作用下生成醛类物质和水。The ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborates(BF4) was synthesized and used as both solvent and electrolyte.Electrochemical reduction of maleic acid in the ionic liquid was studied by cyclic voltammetry(CV),chronoamperometry(CA) and in situ FTIR spectroscopy.The results demonstrated that the reduction of maleic acid on GC electrode is an irreversible process controlled by diffusion.The diffusion coefficient D of maleic acid is determined to be 9.62×10-8 cm2/s.in situ FTIR results illustrated that the reduction of maleic acid in ionic liquids occurs on the carboxyl.The first step is to geaerte radical anions,which are reduced then to aldehyde species and water with two hydrogen ions.国家自然科学基金(批准号:20673091,20833005)~
