First-Principle Calculations on O-Doped Hexagonal Boron Nitride (H-BN) for Carbon Dioxide (CO₂) Reduction into C1...

With the rapid growth of the world population and economy, the greenhouse effect caused by CO₂ emissions is becoming more and more serious. To achieve the "two-carbon" goal as soon as possible, the carbon dioxide reduction reaction is one of the most promising strategies due to its economic and environmental friendliness. As an analog of graphene, monolayer h-BN is considered to be a potential catalyst. To systematically and theoretically study the effect of O doping on the CO₂ reduction catalytic properties of monolayer h-BN, we have perform a series of first-principle calculations in this paper. The structural analysis demonstrates that O preferentially replaces N, leading to decreasing VBM of monolayer h-BN, which is conducive to improving its capability for CO₂ reduction. The preferential CO₂ adsorption sites on monolayer h-BN before and after O doping are the N-t site and B-t site, respectively. O doping increases the adsorption strength of CO₂, which is favorable in the further hydrogenation of CO₂. During the conversion of CO₂ into CO and HCOOH via a two-electron pathway and CH₃OH and CH₄ via a six-electron pathway, O doping can reduce the energy barrier of the rate determining step (RDS) and change the key steps from uphill reactions to downhill reactions, thus increasing the probability of CO₂ reduction. In conclusion, O(N)-doped h-BN exhibits the excellent CO₂ reduction performance and has the potential to be a promising catalyst.