Highly Efficient Ru(II)-based Electrocatalyst for Reduction of Carbon Dioxide to Carbon Monoxide

For the past two centuries, fossil fuels such as natural gas, oil, and coal have been essential for the production of energy and commodity chemicals. For example, around 90% of the energy produced worldwide in 2011 was derived from fossil fuels [1]. The serious problem arising from the mass consumption of fossil resources is the increase in the atmospheric CO2 concentration. In addition, when fossil resources are utilized as chemical resources, most of the synthetic chemicals produced are finally burned and converted into CO2 after they have fulfilled their purpose. It has recently been sounded that the increase in the atmospheric CO2 concentration may induce severe global warming [2]. Therefore, the environmental and economic incentives to develop processes for the conversion of CO2 into fuels and chemicals are enormous. In recent years, many polypyridyl ruthenium complexes have been widely studied for their activity in the electrocatalytic reduction of CO2 to CO [3,4].Herein, we report a new electrocatalyst for CO2 reduction to CO in acetonitrile. The mononuclear ruthenium(II) complex, [Ru(DMF)4(PD)](BF4)2, was synthesized and characterized by spectroscopic methods, cyclic voltammetry, and single-crystal X-ray crystallography. Further, the electrocatalytic activity of the Ru(II) complex was investigated for the 2ē reduction of CO2 to CO in acetonitrile by cyclic voltammetry under different reaction conditions including temperature variation, CO2 concentration, catalyst concentration, and scan rate.