A Density Functional Theory Study of NO Reduction by C3H8 Aided Selective Catalytic Reduction Method

Tezsevin, Ilker
Onay, Deniz
Önal, Işık
In this theoretical work sequential adsorption of H-2 and O-2 on a Ag (7) (+) cluster surface is first studied and Ag (7) (+) H2O2 cluster co-complex thereby obtained is used for the NO reduction process. This cationic charged silver nano cluster simulates small Ag crystals experimentally detected on gamma-Al2O3 support. For NO reduction, three different mechanisms and intermediate steps of these mechanisms reported in experimental literature are examined. Energy profiles, activation barriers and transition states of the reaction steps involved are studied. Some intermediate steps turned out to have high activation barriers. Hence a combined mechanism selected from the favorable steps found in these three mechanisms is proposed. By using this combined mechanism, reduction of NO to N-2 is achieved.


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CO oxidation reaction mechanisms and energetics are examined on adsorbed Pd-4 and Rh-4 clusters and adsorbed Pd and Rh atoms on CeO2 and Ce0.75Zr0.25 O-2 support structures using DFT methods. Activation barriers and TS structures are computed with CI-NEB method. On cluster adsorbed systems, Zr affects CO binding position and O-2 adsorption mode. Energetically, formation of two CO2 molecules without barrier and surface regeneration is possible only on Pd-4-CeO2 surface. With metal atom substituted surfaces, ...
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Citation Formats
I. Tezsevin, D. Onay, M. F. FELLAH, and I. Önal, “A Density Functional Theory Study of NO Reduction by C3H8 Aided Selective Catalytic Reduction Method,” CATALYSIS LETTERS, pp. 964–970, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31007.