Photomethanation of Gaseous CO₂ over Ru/Silicon Nanowire Catalysts with Visible and Near-Infrared Photons

Gaseous CO₂ is transformed photochemically and thermochemically in the presence of H₂ to CH₄ at millimole per hour per gram of catalyst conversion rates, using visible and near-infrared photons. The catalyst used to drive this reaction comprises black silicon nanowire supported ruthenium. These results represent a step towards engineering broadband solar fuels tandem photothermal reactors that enable a three-step process involving i) CO₂ capture, ii) gaseous water splitting into H₂, and iii) reduction of gaseous CO2 by H₂.