The mechanism for CO2 reduction over Fe-modified Cu(100) surfaces with thermodynamics and kinetics: a DFT study

Abstract

The adsorption, activation and reduction of CO₂ over Fe_x/Cu(100) (x = 1–9) surfaces were examined by density functional theory. The most stable structure of CO₂ adsorption on the Fe_x/Cu(100) surface was realized. The electronic structure analysis showed that the doped Fe improved the adsorption, activation and reduction of CO₂ on the pure Cu(100) surface. From the perspective of thermodynamics and kinetics, the Fe₄/Cu(100) surface acted as a potential catalyst to decompose CO₂ into CO with a barrier of 32.8 kJ mol⁻¹. Meanwhile, the first principle molecular dynamics (FPMD) analysis indicated that the decomposition of the C–O1 bond of CO₂ on the Fe₄/Cu(100) surface was only observed from 350 K to 450 K under a CO₂ partial pressure from 0 atm to 10 atm. Furthermore, the results of FPMD analysis revealed that CO₂ would rather decompose than hydrogenate when CO₂ and H co-adsorbed on the Fe₄/Cu(100) surface.