Electrochemical Reduction of Carbon Dioxide in 1-Ethyl-3-Methylimidazolium BF4/Methanol Electrolyte

Carbon dioxide (CO2) can be electrochemically reduced to useful products under mild condition. In recent years, increased attempts have been devoted to use ionic liquid (IL) as the solvents, electrolytes and catalysts for CO2 reduction. However, owing to the high viscosity of ILs, CO2 diffusion in ILs is restrained, lead to low current density of CO2 reduction. To overcome this problem, in present work, we used methanol as the organic solvent to dilute 1-Ethyl-3-Methylimidazolium BF4 ([Bmim]BF4), an commonly used IL in electrochemistry, the obtained [Bmim]BF4/methanol solution have many unique properties, such as low viscosity, high ionic conductivity, high CO2 solubility and low cost. The current density of CO2 reduction reached 14.2 mA/cm(2) at -1.95V (vs SCE) on Ag electrode. Electrochemical reduction of CO2 in [Bmim]BF4/methanol solution provides a hopeful technique for CO2 recycling utilization and renewable electrical energy storage.