Photothermal conversion of CO2 into lower olefins at the interface of the K-promoted Ru/Fe3O4 catalyst

Solar-driven conversion of CO2 to high-value-added chemicals and fuels offers a practical route to alleviate CO2 emissions where photodriven catalytic CO2 hydrogenation toward lower olefins is a great challenge due to the crucial bottleneck of C–C coupling. Here, we report a K-promoted Ru/Fe3O4 catalyst that efficiently drives photothermal catalytic CO2 hydrogenation to lower olefins via the Fischer-Tropsch-to-olefin process, where the production rate reaches 0.63 mmol g−1 h−1 with the highest olefin/paraffin ratio of 10.2. The formation of Ru-FeOx at the interface of Ru nanoparticles and the Fe3O4 support plays a decisive role in forming C–C bonds and determining the hydrocarbon products. The photochemical contribution promotes electron transfer at the interface of K-promoted Ru/Fe3O4, significantly enhances the activation and dissociation of CO2, and abruptly inhibits the hydrogenation of olefins. Therefore, the product distribution and selectivity of olefins are distinctly different from those of the thermal catalysis process.