Synergy of Photo- and Photothermal-catalytic Synthesis of Methyl Propionate from Ethylene and Carbon Dioxide over B-TiO2/Ru

Sustainablelight and CO2 are combined by hydroesterificationreaction for preparing methyl propionate via B-TiO2/Ru as photo- and photothermal-catalysts. Usinggreenhouse gas CO2 as the carbonyl source, thepreparation of methyl propionate (MP) via the synergistic effect ofphoto- and photothermal-catalysis instead of traditional thermal catalysisof ethylene hydroesterification was first proposed. Ru-loaded blackTiO(2) (B-TiO2/Ru) was selected as a photo-and photothermal-catalyst since Ru has been used as an excellent catalystfor hydroesterification, and black TiO2 with a high photothermaleffect can reduce CO2 to more active CO in the hydroesterificationreaction under light irradiation. The excellent photothermal effectsfrom B-TiO2/Ru improve the yield of MP. A seriesof B-TiO2/Ru were successfully prepared and characterizedby X-ray photoelectron spectroscopy, transmission electron microscopy,Fourier transform infrared, Raman spectroscopy, and X-ray diffraction.For the synergistic effect of photo- and photothermal-catalysis ofethylene carbonylation, higher oxygen vacancy density and photothermaleffect of the B-TiO2/Ru catalyst lead to higherreaction efficiency. The ethylene hydroesterification reaction mechanismunder full-spectrum Xe lamp illumination over the B-TiO2/Ru catalyst is discussed.