Theoretical Research On Mechanism Of Catalytic Reduction Of CO₂ By Metal Oxide And Silver

In order to reduce the impact of the "greenhouse effect",electrocatalytic reduction of CO₂ has begun to receive attention.However,due to the lack of suitable electrocatalysts,the development of highly selective catalysts is imminent.Based on density functional theory,this paper theoretically studies the mechanism of metal oxide and Ag synergistic catalytic reduction of CO₂ using Materials Studio software.The study found that the metal and metal oxide electrodes opened a new reaction channel that could not be realized on the pure Ag metal electrode,and further reduced CO₂ to CH₃OH or CH₄.It has also been found that the selectivity of the product is related to the binding ability of the catalyst to O.The final product of the catalyst with strong O binding ability is CH₄,and the final product of the catalyst with weak O binding ability is CH3OH.Based on the previous studies on the effects of different oxide supports,two different catalyst models of Ag surface coverage of 25%,50%and 75%were constructed to influence the effect of different surface coverage on the catalytic effect.The results show that different Ag surface coverage will change the reduction route and product selectivity of the catalyst.From the thermodynamic point of view,all three different Ag surface coverage catalyst reduction paths are based on the HCOO^*path as the main reduction path.However,different surface coverage yields different products.This study predicts that the Ag/ZrO₂ system is superior to Ag/TiO₂,and it is predicted that Ag coverage has an important impact,which has important guiding significance for experimental research and technological development.