CO2 hydrogenation to methanol over Cd4/TiO2 catalyst: Insight into multifunctional interface

Supported metal catalysts have shown to be efficient for CO ₂ conversion due to their multifunctionality and high stability. Herein, we have combined density functional theory calculations with microkinetic modeling to investigate the catalytic reaction mechanisms of CO ₂ hydrogenation to CH ₃OH over a recently reported catalyst of Cd ₄/TiO ₂. Calculations reveal that the metal-oxide interface is the active center for CO ₂ hydrogenation and methanol formation via the formate pathway dominates over the reverse water-gas shift (RWGS) pathway. Microkinetic modeling demonstrated that formate species on the surface of Cd ₄/TiO ₂ is the relevant intermediate for the production of CH ₃OH, and CH ₂O ^# formation is the rate-determining step. These findings demonstrate the crucial role of the Cd-TiO ₂ interface for controlling the CO ₂ reduction reactivity and CH ₃OH selectivity.