Co0-Coδ+ Interface Double-Site-Mediated C-C Coupling for the Photothermal Conversion of CO2 into Light Olefins

Solar-driven CO2 hydrogenation into multicarbon products is a highly desirable, but challenging reaction. The bottleneck of this reaction lies in the C-C coupling of C-1 intermediates. Herein, we construct the C-C coupling centre for C-1 intermediates via the in situ formation of Co degrees-Co delta+ interface double sites on MgAl2O4 (Co-CoOx/MAO). Our experimental and theoretical prediction results confirmed the effective adsorption and activation of CO2 by the Co degrees site to produce C-1 intermediates, while the introduction of the electron-deficient state of Co delta+ can effectively reduce the energy barrier of the key CHCH* intermediates. Consequently, Co-CoOx/MAO exhibited a high C2-4 hydrocarbons production rate of 1303 mu molg(-1)h(-1); the total organic carbon selectivity of C2-4 hydrocarbons is 62.5% under light irradiation with a high ratio (approximate to 11) of olefin to paraffin. This study provides a new approach toward the design of photocatalysts used for CO2 conversion into C2+ products.