Unlocking solar-derived CO2 conversion to hydrocarbons over plasmonic Cu-Fe tandem catalysts under industrially relevant conditions

Solar-driven conversion of CO2 into hydrocarbons offers a sustainable route to carbon-neutral fuels, yet efficient C-C coupling under photo-thermal conditions remains challenging. Here, we report a potassium-promoted Cu2Fe1 tandem catalyst for selective photo-thermal CO2 hydrogenation under industrially relevant conditions. Under illumination at 250 °C and 20 bar, the catalyst achieves 77.4% selectivity towards C2+ hydrocarbons, with a C2-5 hydrocarbon yield of 5.04 mmol g−1 h−1, representing highly competitive performance among reported photo-thermal CO2 hydrogenation systems. Mechanistic studies reveal a tandem pathway in which Cu promotes the reverse water-gas shift reaction to generate CO, followed by Fischer-Tropsch-type hydrocarbon formation over in situ-formed χ-Fe5C2. In situ DRIFTS, in situ XRD and CO-TPR analyses further show that light-induced non-thermal effects, together with localized heating at the Cu-Fe interface, facilitate carbide formation and accelerate key intermediate evolution. Solar-derived conversion of CO2 into hydrocarbons offers a sustainable alternative to mitigate carbon emissions but achieving efficient C-C coupling under photothermal conditions remains challenging. Here, we report a potassium-promoted Cu2Fe1 tandem catalyst that enables highly selective CO2-to-hydrocarbons conversion under industrially relevant conditions.