TY - JOUR
T1 - DFT Study of NO Reduction Process on Ag/γ-Al2O3 Catalyst: Some Aspects of Mechanism and Catalyst Structure
AU - Matulis, Vitaly E.
AU - Ragoyja, Ekaterina G.
AU - Ivashkevich, Oleg A.
AU - Lyakhov, Dmitry
AU - Michels, Dominik L.
N1 - KAUST Repository Item: Exported on 2020-12-30
Acknowledgements: All Gaussian16 computations were performed on KAUST’s Ibex HPC. The authors thank the KAUST Supercomputing Core Lab team for assistance with execution tasks on Skylake nodes.
PY - 2020/12/23
Y1 - 2020/12/23
N2 - Catalysts based on Ag/γ-Al2O3 are perspective systems for practical implementation of catalytic NO reduction. Nevertheless, the mechanism and regularities of this process have still not been fully investigated. Herein, we present the results of quantum-chemical research of the Ag/γ-Al2O3 catalyst surface and some aspects of the NO reduction mechanism on it. Proposed calculation methods using DFT and cluster models of the catalyst surface are compared and verified. The possibility of existence of small adsorbed neutral and cationic silver clusters on the surface of the catalyst is shown. It is demonstrated that NO adsorption on these clusters is energetically favorable, in the form of both monomers and dimers. The scheme of NO selective catalytic reduction (SCR) that explains increasing of N2O side-product amount on catalysts with silver fraction more than 2 wt % is proposed. The feasibility of this scheme is justified with calculated data. Some recommendations that allow decreasing amounts of N2O are developed.
AB - Catalysts based on Ag/γ-Al2O3 are perspective systems for practical implementation of catalytic NO reduction. Nevertheless, the mechanism and regularities of this process have still not been fully investigated. Herein, we present the results of quantum-chemical research of the Ag/γ-Al2O3 catalyst surface and some aspects of the NO reduction mechanism on it. Proposed calculation methods using DFT and cluster models of the catalyst surface are compared and verified. The possibility of existence of small adsorbed neutral and cationic silver clusters on the surface of the catalyst is shown. It is demonstrated that NO adsorption on these clusters is energetically favorable, in the form of both monomers and dimers. The scheme of NO selective catalytic reduction (SCR) that explains increasing of N2O side-product amount on catalysts with silver fraction more than 2 wt % is proposed. The feasibility of this scheme is justified with calculated data. Some recommendations that allow decreasing amounts of N2O are developed.
UR - http://hdl.handle.net/10754/666745
UR - https://pubs.acs.org/doi/10.1021/acs.jpcc.0c08417
U2 - 10.1021/acs.jpcc.0c08417
DO - 10.1021/acs.jpcc.0c08417
M3 - Article
SN - 1932-7447
JO - The Journal of Physical Chemistry C
JF - The Journal of Physical Chemistry C
ER -