Tuning the selectivity of the CO2 hydrogenation reaction using boron-doped cobalt-based catalysts

Abstract

Direct CO₂ hydrogenation to value-added chemicals is a promising path toward realizing the “carbon-neutral” goal. However, controlling the selectivity of CO₂ hydrogenation toward desired products (e.g., CO and CH₄) using non-precious metal-based catalysts is important but challenging. It is imperative to explore catalysts with high activity and stability. Herein, boron-doped cobalt nanoparticles supported on H-ZSM-5 were devised for CO₂ hydrogenation to produce CO in a gas–solid flow system. Our results demonstrate that boron doping not only increases the CO₂ adsorption capability of the catalyst but also optimizes the electronic state of Co for CO desorption during hydrogenation process. As a result, the boron-doped cobalt catalysts displayed an enhanced CO selectivity of 94.5% and a CO₂ conversion rate of 45.6%, which is much higher than that of Co-ZSM-5 without boron doping. This study shows that the strategic design of metal borides is important for controlling the selectivity of desired products in the CO₂ hydrogenation reaction.