Multistep Reaction Pathway for CO₂ Reduction on Hydride-Capped Si Nanosheets

Silicon hydride, as a new efficient catalyst for CO₂ conversion to CO, is receiving ever-increasing attention. Thus, a precise catalytic mechanism is needed to provide a guideline for the design of new efficient catalysts based on silicon hydride. Qian et al. recently proposed a one-step mechanism for the catalytic process. The present work, based on the recently proposed WMS and revM06 quantum mechanical model chemistries, provides a multistep mechanism that has a lower free energy of activation than the one-step model. A key point in favor of the new mechanism is that it is consistent with experimental details of the infrared spectrum that cannot be explained by the previous mechanism.