Zeolitic‐Imidazolate Framework Derived Intermetallic Nickel Zinc Carbide Material as a Selective Catalyst for CO2 to CO Reduction at High Pressure

Abstract The conversion of CO 2 into CO is an important step in CO 2 utilization to achieve clean fuels and value‐added chemicals. Herein, we explored the pyrolysis of zeolitic imidazolate framework‐8 (ZIF‐8) loaded with different amounts of Ni 2+ to obtain Ni−Zn carbide (Ni 3 ZnC) embedded in N‐doped carbon. Ni is present in the intermetallic compound, while Zn excess remains on the N‐doped carbon. The Ni 3 ZnC phase catalyzes the selective hydrogenation of CO 2 into CO via the reverse water gas shift reaction, reaching 100 % CO selectivity at ∼30 % CO 2 conversion at 450 °C and atmosphere pressure (CO 2 : H 2 =1 : 4, GHSV=30000 mL g cat −1 h −1 ). The methanation reaction of CO 2 /CO, which is usually favored over Ni catalysts, is suppressed. The selectivity to CO at the expense of CH 4 is related to the stability of chemisorbed CO in the Ni 3 ZnC surface, which is lower compared to Ni surfaces. The Ni 3 ZnC@NC catalyst is selective towards CO over a wide range of conditions, including high pressure, that is usually required for the conversion of CO to hydrocarbons and alcohols via the Fisher‐Tropsch synthesis (FTS) process. Contrarily, a classical Ni/SiO 2 catalyst prepared by impregnation produces CH 4 under high pressure.