Density Functional Studies of the Adsorption and Dissociation of CO₂Molecule on Fe(111) Surface

Abstract

Spin-polarized density functional theory calculation was carried out to characterize the adsorption and dissociation of CO(2) molecule on the Fe(111) surface. It was shown that the barriers for the stepwise CO(2) dissociation reaction, CO(2(g)) --> C(a) + 2O(a), are 21.73 kcal/mol (for OC-O bond activation) and 23.87 kcal/mol (for C-O bond activation), and the entire process is 35.73 kcal/mol exothermic. The rate constants for the dissociative adsorption of CO(2) have been predicted with variational RRKM theory, and the predicted rate constants, k(CO(2)) (in units of cm(3) molecule(-1) s(-1)), can be represented by the equations 2.12 x 10(-8)T(-0.842) exp(-0.258 kcal mol(-1)/RT) at T = 100-1000 K. To gain insights into high catalytic activity of the Fe(111) surface, the interaction nature between adsorbate and substrate is also analyzed by the detailed electronic analysis.

First-Principles Design of Iron-Based Active Catalysts for Adsorption and Dehydrogenation of H2O Molecule on Fe(111), W@Fe(111), and W2@Fe(111) Surfaces

“…To ensure the reliability of the computational method in our work, we first calculated some significant characters of bulk iron, tungsten, gas-phase H 2 O, and OH molecules. Previously, Chen et al have already predicted the lattice parameter of bulk iron at GGA-rPBE level of theory, and their result represented 2.836 Å, which approaches the experimental value 2.866 Å. For the bulk tungsten, the lattice parameters of bulk at GGA-rPBE functional have also been reported by Chen et al, and the result shows 3.181 Å, which is closely with the experimental value of 3.165 Å.…”

Computational investigation of NH3adsorption and dehydrogenation on a W-modified Fe(111) surface

“…Previously, Chen et al 36 calculated the lattice parameters of bulk Fe via the rPBE functional (with the consideration of spin polarization) and found its lattice constant, 2.836 Å, which approaches the experimental value, 2.866 Å. They also studied the magnetic moment of the bulk Fe, 2.23 m B , which agrees satisfactorily with the experimental value, 2.22 m B .…”

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

“…In methanol synthesis : Since CO 2 hydrogenation on Fe surfaces seem to proceed via an associative pathway in RWGS, the formate intermediate may also lead to the production of methanol. Chen et al . studied Fe(111) surface for decomposition of CO 2 with PW‐DFT method.…”

“…In methanol synthesis: Since CO 2 hydrogenation on Fe surfaces seem to proceed via an associative pathway in RWGS, the formate intermediate may also lead to the production of methanol. Chen et al [197] studied Fe(111) surface for decomposition of CO 2 with PW-DFT method. Their data show that isomers FeCO 2 (S-μ 3 À C,O,O'), FeCO(S-η1À C) and FeX(T,S-μ 2 À X) or FeX(B-μ 3 À X), for X = C and O atoms, are energetically favored among calculated structures of Fe(111)/CO 2 , Fe(111)/CO and Fe (111)/X.…”