Alkylsilane-extended hydrogen migration enhanced photothermal Sabatier reaction

Hydrogen migration is a process of key importance in hydrogenation reactions. In past decades, surface oxygen has been considered the major pathway for hydrogen migration, whereas the reduction reaction may occur to yield water and inhibit the migration. Thus, extending hydrogen migration via precise surface decoration could potentially be beneficial to the activity of hydrogenation reactions, yet it remains challenging. Herein, the Sabatier reaction is chosen as the archetype reaction, in which the catalytic performance is highly dependent on the activity of hydrogen migration. By decorating a minor amount of non-reducible alkylsilane over the benchmark Ni/CeO2 catalyst, the hydrogen activation, migration, and overall hydrogenation reaction have been enhanced significantly. As a result, with the help of the exothermic nature of the Sabatier reaction, the solely solar-driven reaction can be conducted with a CO2 single pass conversion of 99.9%, a near-unity CH4 selectivity, and an energy conversion efficiency of ~25.0% for outdoor practice. Hydrogen movement on catalyst surfaces shapes how effectively reactions form useful products. This study shows that subtle surface tuning greatly boosts hydrogen flow and enables highly efficient solar-driven conversion of carbon dioxide to methane.