Boosting CO₂ Hydrogenation Activity by Carbon Coating over a Nickel Catalyst

Earth-abundant metal-based materials play a crucial role in catalyzing the production of sustainable chemicals and fuels, offering a cost-effective and scalable alternative to precious metals. Among earth-abundant metals, nickel-based catalysts show the biggest potential for industrial applications. Herein, a series of nickel-based catalysts was synthesized by thermal decomposition of Ni complexes over an alumina support under argon, thereby forming a thin carbon layer around the monodispersed nickel particles. By selecting a ligand, the particle size could be tuned (from 10 to 5 nm), and the C-layer structure could be modified by introducing dopants such as N. The solids obtained were used as catalysts for CO₂ hydrogenation. The material in which Ni particles with a covering C-layer overperformed the "naked" Ni particles at low temperatures. This may be related to the smaller Ni particles obtained from complex decomposition and a synergistic effect between these carbon layers and the Ni particles.