Fast-Response Nickel-Promoted Indium Oxide Catalysts for Carbon Dioxide Hydrogenation from Intermittent Solar...

Construction of a "net-zero-emission" system through CO₂ hydrogenation to methanol with solar energy is an eco-friendly way to mitigate the greenhouse effect. Traditional CO₂ hydrogenation demands centralized mass production for cost reduction with mass water electrolysis for hydrogen supply. To achieve continuous reaction with intermittent and fluctuating flow of H₂ on a small-scale for distributed application scenarios, modulating the catalyst interface environment and chemical adsorption capacity to adapt fluctuating reaction conditions is highly desired. This paper describes a distributed clean CO₂ utilization system in which the surface structure of catalysts is carefully regulated. The Ni catalyst with unsaturated electrons loaded on In₂ O₃ can reduce the dissociation energy of H₂ to overcome the slow response of intermittent H₂ supply, exhibiting a faster response (12 min) than bare oxide catalysts (42 min). Moreover, the introduction of Ni enhances the sensitivity of the catalyst to hydrogen, yielding a Ni/In₂ O₃ catalyst with a good performance at lower H₂ concentrations with a 15 times adaptability for wider hydrogen fluctuation range than In₂ O₃ , greatly reducing the negative impact of unstable H₂ supplies derived from renewable energies.