Photoelectrochemical reduction of CO2 over Ru/Mn/Co trimetallic catalysts supported anatase TiO2 under visible light irradiation

Excessive emission of carbon dioxide (CO2) into the environment in addition to depletion of natural fossil fuel leads to the environmental pollution and energy crisis. Therefore, the photelectroreduction of CO2 is a suitable and versatile technique to convert CO2 gas into valuable organic products. Herein, Ru/Mn/Co (1:13:13) supported anatase TiO2 has been prepared using precipitation method and tested for photoelectrochemical reduction of CO2 into formic acid in aqueous and N,N-dimethylformamide (DMF) under visible light. Incorporation of Ru, Mn, and Co successfully reduced the bandgap to 1.66 eV and shifted the light absorption to the visible region with effective suppression of charge carriers recombination which is injurious to the photocatalytic reaction resultant in better photocatalytic performance. The photocurrent density in the aqueous medium is higher than DMF with a value of 12 mu A cm(-2) vs. Ag/AgCl. Stable photocurrent form chronoamperometry indicative of better product selectivity toward formic acid with Faradaic efficiency in aqueous and DMF are 0.8% and 2.23%, respectively. [GRAPHICS] .