Density Functional Calculations on the Hydrogenation of Carbon Dioxide on Fe(111) and W(111) Surfaces

Abstract

With quantum-chemical calculations, we investigated the hydrogenation of a CO2 molecule on Fe(111) and W(111) surfaces using the density functional theory (DFT) with the projector-augmented wave (PAW) approach in periodic boundary condition. The structures and geometric parameters of the hydrogenation products, and the potential-energy surfaces, were calculated. It was shown that similar reaction paths for the hydrogenation of CO2 on Fe(111) and W(111) surfaces were found but with disparate energies. The rate-controlling energy barriers from M-CO2 (M = Fe, W) plus H atom to form formate (HCOO) and carboxyl (COOH) on a Fe(111) surface are 0.37 and 1.69 eV, respectively, but 0.54 and 2.79 eV, respectively, on a W(111) surface. The most probable path for the hydrogenation of a CO2 molecule on either the Fe(111) or W(111) surface is the formation of a formate-vertical structure. To understand the interaction between adsorbates and surfaces, we calculated the Bader charges and analyzed the local densities of states.

Recent Developments in the Modelling of Heterogeneous Catalysts for CO2 Conversion to Chemicals

“…Their simulations of CO 2 dissociation on Fe(111) surface showed that the catalytic process is likely to proceed via a three-step mechanism. Li et al [198] with the use of PAW method in conjunction with the rPBE functional studied microkinetic modelling of CO 2 hydrogenation on Fe(111) surface. They found out that the most probable path for the hydrogenation of CO 2 on Fe(111) surface is the formation of a formate-vertical structure.…”

“…Their simulations of CO 2 dissociation on Fe(111) surface showed that the catalytic process is likely to proceed via a three‐step mechanism. Li et al . with the use of PAW method in conjunction with the rPBE functional studied microkinetic modelling of CO 2 hydrogenation on Fe(111) surface.…”

H2‐free Synthesis of Aromatic, Cyclic and Linear Oxygenates from CO2

“…It is possible that the reaction proceeds via either formate (HCOO) [Scheme (a)] or carboxylate (COOH) as an intermediate [Scheme (b)]. It has previously been reported that the adsorption of HCOO on iron surfaces is more stable than that of carboxylate . Thus, it may be expected that the first step in the mechanism of formation of heptanal and 2‐octanone is the formation of formate.…”

“…It is possible that the reactionp roceeds via either formate (HCOO)[ Scheme 1(a)] or carboxylate (COOH) as an intermediate [Scheme 1(b)].I th as previously been reported that the adsorptiono fH COO on iron surfaces is more stable than that of carboxylate. [69,70] Thus, it may be expected that the first step in the mechanism of formation of heptanal and 2-octanone is the formation of formate.H owever,i th as been observed (e.g., Figure2)t hat liquid species formed during the hydrothermal conversion of CO 2 in the present work maintained the C=O double bond. This is consistentw ith the carboxylate mechanism for which the C=Ob ond is preserved through all steps.…”

Anti-corrosive properties of quercetin and its derivatives on Fe(111) surface: a quantum chemical approach

“…Recent experimental studies showed that quercetin can used as a potential corrosion inhibitors against C38 steel [21] due to the presence of heteroatoms. Fe(111) surface was chosen for this study, as it is more reactive and has a very open surface structure [50,51]. Due to the planar structure of quercetin backbone, a parallel interaction between the metal surface and the molecule was expected to occur which would enable facile adsorption of the molecule.…”