A comparison of water-gas shift reaction on ZnO surface and 6Cu cluster deposited over ZnO surface using
Vo Thanh Cong1, Nguyen Van Son2, Do Quy Diem2
1Faculty of Chemical Engineering, Industrial University of Ho Chi Minh City, Ho Chi Minh City, Vietnam. vothanhcong@iuh.edu.vn.
Abstract:
This work has presented a calculated study of the water-gas shift reaction (WGSR) performing on the models of ZnO only and six-atomic copper cluster deposited on the ZnO surfaces (6Cu/ZnO) using density functional theory (DFT). The most stable configurations of ZnO and 6Cu/ZnO surfaces were found and used for the mechanism calculations of WGSR. The carboxyl mechanism of WGSR was proposed to find the reaction pathway. Based on this pathway, WGSR occurred at the elementary reaction of COOH intermediate formation as the rate-controlling step on 6Cu/ZnO surface, and the elementary reaction of H-H association as the rate-controlling step on ZnO surface, in which the highest activation energies were calculated as 1.05 eV and 1.56 eV for 6Cu/ZnO and ZnO surfaces, respectively. These calculations indicated that the 6Cu/ZnO was more favorable and more effective than ZnO as a catalyst for WGSR. In addition, the nature of bonds of CO and H2O adsorption on ZnO and 6Cu/ZnO surfaces was also analyzed using the local density of states (LDOS) and electron density difference (EDD) methods.
More Related Videos
06:39Aerosol-assisted Chemical Vapor Deposition of Metal Oxide Structures: Zinc Oxide Rods
Published on: September 14, 2017
11:38In situ FTIR Spectroscopy as a Tool for Investigation of Gas/Solid Interaction: Water-Enhanced CO2 Adsorption in UiO-66 Metal-Organic Framework
Published on: February 1, 2020
Related Concept Videos
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...