A DFT study on CO oxidation on Pd-4 and Rh-4 clusters and adsorbed Pd and Rh atoms on CeO2 and Ce(0.75)Z(r0.25)O(2) supports for TWC applications

Date

2013-11-15

Author

Gerceker, Duygu
Önal, Işık

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

181
views

0
downloads

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, Pd substituted Ce0.75Zr0.25O2 and CeO2 supports are found to be capable of completing catalytic cycle with consecutive CO oxidations by creating and filling surface oxygen vacancies.

Subject Keywords

CO oxidation, Density functional theory, Three way catalysts, Ceria Noble metals

URI

https://hdl.handle.net/11511/30490

Journal

APPLIED SURFACE SCIENCE

DOI

https://doi.org/10.1016/j.apsusc.2013.09.016

Collections

Graduate School of Natural and Applied Sciences, Article

Suggestions

OpenMETU
Core

A Density Functional Theory Study of NO Reduction by C3H8 Aided Selective Catalytic Reduction Method Tezsevin, Ilker; Onay, Deniz; FELLAH, MEHMET FERDİ; Önal, Işık (2015-03-01) 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...
A DFT Study of Direct Oxidation of Benzene to Phenol by N2O over [Fe(mu-O)Fe](2+) Complexes in ZSM-5 Zeolite Fellah, Mehmet Ferdi; Pidko, Evgeny A.; van Santen, Rutger A.; Önal, Işık (2011-05-19) Density functional theory (DFT) calculations were carried out in a study of the mechanism of benzene oxidation by N2O to phenol over an extra framework dimeric [FeOFe](2+) species in ZSM-5 zeolite represented by a [Si6Al2O9H14(Fe(mu-O)Fe)] cluster model. The catalytic reactivity of such a binuclear species is compared with that of mononuclear Fe2+ and (FeO)(+) sites in ZSM-5 investigated in our earlier works at the same level of theory (J. Phys. Chem. C 2009, 113, 15307; 2010, 114, 12580). The activation en...
A quantum chemical study of nitric oxide reduction by ammonia (SCR reaction) on V2O5 catalyst surface

Soyer, Sezen; Uzun, Alper; Senkan, Selim; Önal, Işık (2006-12-15)

The reaction mechanism for the selective catalytic reduction (SCR) of nitric oxide by ammonia on (010) V2O5 surface represented by a V2O9H8 cluster was simulated by means of density functional theory (DFT) calculations performed at B3LYP/6-31G** level. The computations indicated that SCR reaction consisted of three main parts. For the first part, ammonia activation on V2O5 was investigated. Ammonia was adsorbed on Bronsted acidic V-OH site as NH4+ species by a non-activated process with an exothermic relati...
A density functional theory study of partial oxidation of propylene on Cu2O(001) and CuO(001) surfaces Duzenli, Derya; Atmaca, Deniz Onay; Gezer, Miray Gulbiter; Önal, Işık (2015-11-15) This work theoretically investigates propylene epoxidation reaction on Cu2O(001) and CuO(001) surfaces using periodical DFT method to determine the active copper species within the reaction mechanism. The transition states and energy profiles are calculated for the formation of surface intermediates such as oxametallopropylene (OMP) over Cu2O(0 0 1) and oxygen bridging (OB) over CuO(0 0 1) and allylic H-stripping reaction (AHS) over both surfaces as well as for formation of products. Propylene oxide (PO) an...
A van der Waals DFT study of chain length dependence of alkanethiol adsorption on Au(111): physisorption vs. chemisorption Mete, Ersen; Yortanli, Merve; Danışman, Mehmet Fatih (2017-06-07) The energetics and structures of physisorbed and chemisorbed alkanethiols on Au(111) have been systematically investigated up to 10 carbon atoms using van der Waals (vdW) corrected density functional theory (DFT) calculations. The role of chain length, tilting angle and coverage on the adsorption characteristics has been examined to elucidate the energetics and plausible transformation mechanisms between lying down and standing up phases. Coverage and size dependent chain-chain electronic interactions count...

Citation Formats

D. Gerceker and I. Önal, “A DFT study on CO oxidation on Pd-4 and Rh-4 clusters and adsorbed Pd and Rh atoms on CeO2 and Ce(0.75)Z(r0.25)O(2) supports for TWC applications,” APPLIED SURFACE SCIENCE, pp. 927–936, 2013, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/30490.