Carbon Dioxide Fixation as Carbon Nanofiber by Catalytic Hydrogenation on a Sodium Promoted Ni/Al2o3 Catalyst: Kinetics, Active Phase and Reaction Mechanism

<div data-language="eng" data-ev-field="abstract">This study presents a novel carbon fixation technology that converts CO2 into valuable carbon nanofibers (CNFs) using a NiNax/Al2O3 catalyst. The results reveal that NaO2, which covers the Ni/Al2O3 catalyst, plays a crucial role in catalyzing the hydrogenation reaction of CO2 to produce CO, CH4, and CNFs. Carbon deposition on the NiNax/Al2O3 catalyst did not affect the catalytic activity of CO2 hydrogenation, which is noteworthy. The NiNax/Al2O3 catalyst could potentially provide significant bifunctional benefits, such as high CO production and valuable carbon materials. The CNFs were likely formed at the interfacial sites between NiNax and Al2O3. The CNF formation involves the reaction of H2 bound to Ni with adsorbed CO2 to form hydrogen carbonate species, which further generate CNFs. The reduction of CO2 to CNFs was facilitated by the transfer of electrons from Al3+ species to interfacial sites between NiNax and Al2O3.<br/></div> &copy; 2023, The Authors. All rights reserved.