Molecular-Level Insights into Adsorption and Diffusion Properties of CO and CO2 on Pt-Supported Graphene

The adsorption and diffusion of gas molecules in heterogeneouscatalytic reactions are greatly influenced by various factors suchas temperature, pressure, and catalyst microstructures. To clarifythe role of controlling factors, the adsorption and diffusion behaviorsof CO2 and CO in the supported Pt system were investigatedby multi-scale simulation. The adsorption number of molecules andadsorption energies calculated by molecular dynamics and density functionaltheory, respectively, indicate that Pt has a stronger adsorption forCO. The difference in the adsorption number is proportional to thenumber of adsorption sites and has a volcanic relationship with temperature.The diffusion coefficient of CO molecules varies more dramaticallywith temperature. Furthermore, the generalized formula related diffusioncoefficient with temperature, pressure, and surface atom number ofnanoparticles was further validated based on simulation data. Thiswork provides insights into the diffusion modulation of gas moleculesvia the structural design of catalysts and regulation of reactionconditions.