Influence of Ag Metal Dispersion on the Catalyzed Reduction of CO₂ into Chemical Fuels over Ag–ZrO₂ Catalysts

Abstract

Metal/metal oxide catalysts reveal unique CO 2 adsorption and hydrogenation properties in CO 2 electroreduction for the synthesis of chemical fuels. The dispersion of active components on the surface of metal oxide has unique quantum effects, significantly affecting the catalytic activity and selectivity. Catalyst models with 25, 50, and 75% Ag covering on ZrO 2 , denoted as Ag 4 /(ZrO 2 ) 9 , Ag 8 /(ZrO 2 ) 9 , and Ag 12 /(ZrO 2 ) 9 , respectively, were developed and coupled with a detailed investigation of the electronic properties and electroreduction processes from CO 2 into different chemical fuels using density functional theory calculations. The dispersion of Ag can obviously tune the hybridization between the active site of the catalyst and the O atom of the intermediate species CH 3 O * derived from the reduction of CO 2 , which can be expected as the key intermediate to lead the reduction path to differentiation of generation of CH 4 and CH 3 OH. The weak hybridization between CH 3 O * and Ag 4 /(ZrO 2 ) 9 and Ag 12 /(ZrO 2 ) 9 favors the further reduction of CH 3 O * into CH 3 OH. In stark contrast, the strong hybridization between CH 3 O * and Ag 8 /(ZrO 2 ) 9 promotes the dissociation of the C–O bond of CH 3 O * , thus leading to the generation of CH 4 . Results provide a fundamental understanding of the CO 2 reduction mechanism on the metal/metal oxide surface, favoring novel catalyst rational design and chemical fuel production.

Recent Advances Hydrogenation of Carbon Dioxide to Light Olefins over Iron-Based Catalysts via the Fischer–Tropsch Synthesis

“…In recent years, the excessive use of fuels such as oil, coal, and natural gas has greatly contributed to the development of the economy and human society, but the increasing carbon dioxide emissions in the course of development have also brought about various environmental challenges, such as the greenhouse effect, ocean acidification, and climate anomaly. − Despite CO 2 being a greenhouse gas, CO 2 is a nontoxic carbon source that provides a fungible pathway to produce high-value-added products. , The direct conversion of CO 2 into value-added products is not only conducive to alleviating environmental issues caused by excessive CO 2 emission, but also realizes the resource utilization of CO 2 . − Therefore, CO 2 hydrogenation to value-added chemicals is an excellent way to reduce CO 2 concentrations and arouse the interest of researchers. − …”

“… 6 − 10 Therefore, CO 2 hydrogenation to value-added chemicals is an excellent way to reduce CO 2 concentrations and arouse the interest of researchers. 11 − 13 …”