Pd atomic layer coating enhances CO2 hydrogenation to CH3OH fuel on Cu@Pd(111) core-shell structure catalyst

Abstract

CO2 hydrogenation to methanol can convert greenhouse gases and hydrogen into high value-added liquid fuels, which can be used as a promising hydrogen storage technology, it is of great significance for mitigating the greenhouse effect and energy crisis. In this paper, density functional theory is used to study the effect of Pd atomic layer coating on the activation energy barrier and selectivity in CO2 hydrogenation to methanol. The Pd atomic layer coating can effectively increase the adsorption strength of the intermediate substance and the catalyst surface, the adsorption energy of H* is increased from − 3.50 to − 3.63 eV, and the adsorption energy of COOH* increases by 0.59 eV, properly increasing the adsorption energy is conducive to the progress of catalysis. The Pd atom coating is conducive to the activation and hydrogenation of CO2 and the dissociation of hydrogen, the activation energy barrier of the rate-limiting step is reduced from 1.71 to 1.00 eV, and the energy barrier of H2 dissociation is reduced by 0.27 eV. Cu@Pd(111) enhanced the electron delocalization and increased the catalytic activity. Besides, Pd atom coating suppresses the production of by-product CO, the adsorption energy of CO* increased from − 0.77 to − 1.76 eV, and the energy barrier for CO* production increased by 0.80 eV, inhibition of by-products is conducive to further improved methanol selectivity.