CAO Fan, SU Sheng, XIANG Jun, et al. NO/NH3 adsorption properties on γ-Al2O3 (110) surface during SCR process[J]. CIESC Journal, 2014, (10): 4056-4062. DOI: 10.3969/j.issn.0438-1157.2014.10.040.
CAO Fan, SU Sheng, XIANG Jun, et al. NO/NH3 adsorption properties on γ-Al2O3 (110) surface during SCR process[J]. CIESC Journal, 2014, (10): 4056-4062. DOI: 10.3969/j.issn.0438-1157.2014.10.040.DOI:
γ-Al2O3 is an outstanding catalyst carrier and has been widely used in the SCR (selective catalytic reduction) catalyst study. The adsorption and reaction properties of NO/NH3 on the bare and defective γ-Al2O3 (110) surface were studied by the DFT (density functional theory) method. The corresponding microscopic parameters
such as adsorption energies
bond length
changes of net charge and PDOS (partial density of states) were calculated. NO could be adsorbed on the bare (110) surface weakly
and it was more inclined to be adsorbed on the top sites of O2c. NH3 could be adsorbed strongly on top sites of Al. The rate-determining step of SCR reaction was the -NH2NO decomposition
while the largest energy barrier reached 235.75 kJ·mol-1. For the defective (110) surface with the oxygen vacancy
NO and NH3 could be both adsorbed strongly on the surface
and NH3 could also decompose into NH2 and H directly in this situation. The largest energy barrier of SCR reaction in this situation was much lower
indicating that the presence of oxygen vacancy could promote SCR reaction proceeding.