[NH2-emim]Br/[Bmim]BF4离子液体中二氧化碳的电化学还原

以2-溴乙胺氢溴酸和N-甲基咪唑盐为原料合成了氨基功能化离子液体1-（2-胺乙基）-3-甲基咪唑溴盐（NH₂-emim]Br），用¹H NMR和IR对所制备的离子液体进行了表征，测得25℃下NH₂-emim]Br的黏度26.691 Pa·s、电导率0.1130 mS·cm^-1，CO₂的溶解饱和度82%（摩尔分数），将不同含量的NH₂-emim]Br与Emim]BF₄、Bmim]BF₄、Bmim]PF₆组成二元复合离子液体，并用于CO₂电化学还原研究，循环伏安研究表明，CO₂在NH₂-emim]Br（0.5%）-Bmim]BF₄复合离子液体中的还原峰电位较Bmim]BF₄正移0.4 V，还原峰电流增大9倍，黏度降低为0.08227 Pa·s，电导率增大至1.317 mS·cm^-1，是一种较好的CO₂电化学还原离子液体体系。

Electrochemical reduction of CO2 in [NH2-emim]Br/[Bmim]BF4 ionic liquid composite

Amine-functionalized ionic liquid, 1-(2-aminoethyl)-3-methyl imidazolium bromide (NH₂-emim]Br), was synthesized from 2-bromoethylamine hydrobromide and N-methyl imidazole salt at reflux condition and characterized by ¹H NMR and IR. Viscosity, electric conductivity and saturated carbon dioxide solubility in NH₂-emim]Br ionic liquid measured at 25℃ were 26.691 Pa·s, 0.1130 mS·cm^-1 and 82% by molar ratio, respectively. Binary ionic liquid composites of NH₂-emim]Br/Emim]BF₄, NH₂-emim]Br/Bmim]BF₄, and NH₂-emim]Br/Bmim]PF₆ were prepared at different mass ratios and used for electrochemical reduction of CO₂. The results of cyclic voltammetry at room temperature showed that peak current of CO₂ reduction in NH₂-emim]Br (0.5%)-Bmim]BF₄ was increased about 9 times than that in Bmim]BF₄ and reduction peak potential was shifted positively by 0.4 V. With viscosity decrease to 0.08227 Pa·s and electrical conductivity increase to 1.317 mS·cm^-1, the binary ionic liquid composite is a good ionic liquid system for CO₂ electrochemical reduction.