Enhanced dry reforming of CO2 and CH4 on photothermal catalyst Ru/SrTiO3

CH4 and CO2, which are greenhouse gases, can be converted into valuable syngas through the solar-powered photothermal dry reforming of methane (DRM); this process also facilitates the collection and storage of solar energy. However, conventional photothermal catalysts insufficient catalytic activity for light enhancement at high temperatures. Herein, we report a photothermal catalyst Ru/SrTiO3. The yields of CO and H2 were 1.4–1.5 times those obtained using the thermocatalytic process at 600 ℃ and under 300-W xenon lamp irradiation. Based on in situ–irradiated X-ray photoelectron spectroscopy and density functional theory calculations, light can induce electron transfer from SrTiO3 to Ru in Ru/SrTiO3 catalysts and participate in CH4 dehydrogenation and H2 generation, lowering its reaction energy barrier. Moreover, photogenerated electrons can suppress the occurrence of inverse water–gas reaction. This study clarifies the mechanism of the photothermal DRM, providing a useful guide for the future solar photothermal conversion of greenhouse gases.