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
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) and acetone are obtained through OMP and OB surface intermediates and acrolein generation is observed through allylic H-stripping reaction (AHS). The calculations revealed that the corresponding surface intermediates for epoxidation reaction need to overcome an activation barrier of 13 kcal/mol over CuO surface whereas they occur without an energy barrier over Cu2O surface indicating the higher activity of Cu+ species. Acrolein is also found to be a thermodynamically more favorable product for both surfaces especially over CuO surface due to the presence of more surface oxygen atoms on which the basicity has been evaluated by the adsorption of sulfur dioxide. This indicates that the lattice oxygen inherent in both surface types does not participate in PO production.


A density functional theory study of propylene epoxidation on RuO2(110) surface
Atmaca, Deniz Onay; Duzenli, Derya; Ozbek, M. Olus; Önal, Işık (2016-11-01)
Propylene epoxidation is investigated on RuO2(110) and oxygen added RuO2-O-ot(110) surfaces by periodic DFT computational method. The desired product propylene oxide (PO) as well as the undesired products acetone (AC) or propionaldehyde (PA) form on both surfaces through either surface intermediate oxometallopropylene (OMMP) or direct oxygen insertion mechanisms. On RuO2(110) surface, nucleophilic lattice oxygen at bridge position (O-br) favors the stable surface intermediate mechanism where high energy req...
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...
Investigation of ruthenium-copper bimetallic catalysts for direct epoxidation of propylene: A DFT study
Kizilkaya, Ali Can; Senkan, Selim; Önal, Işık (2010-09-01)
Propylene epoxidation reactions are carried out on Ru-Cu(1 1 1) and Cu(1 1 1) surfaces with periodic density functional theory (DFT) calculations. Ru-Cu(1 1 1) surface is modeled as Cu(1 1 1) monolayer totally covering the Ru(0 0 0 1) surface underneath, in accordance with the literature. It is shown that the Ru-Cu(1 1 1) surface is ineffective for propylene oxide formation since it has a lower energy barrier (0.48 eV) for the stripping of the allylic hydrogen of propylene and a higher energy barrier (0.92 ...
A van der Waals density functional investigation of carboranethiol self-assembled monolayers on Au(111)
Yılmaz, Ayşen; Danışman, Mehmet Fatih (2016-05-14)
Isolated and full monolayer adsorption of various carboranethiol (C2B10H12S) isomers on the gold(111) surface has been investigated using both the standard and van der Waals density functional theory calculations. The effect of different molecular dipole moment orientations on the low energy adlayer geometries, the binding characteristics and the electronic properties of the self-assembled monolayers of these isomers has been studied. Specifically, the binding energy and work function changes associated wit...
A DFT study on the [VO](1+)-ZSM-5 cluster: direct methanol oxidation to formaldehyde by N2O
FELLAH, MEHMET FERDİ; Önal, Işık (2013-01-01)
The mechanism of direct oxidation of methanol to formaldehyde by N2O has been theoretically investigated by means of density functional theory over an extra framework species in ZSM-5 zeolite represented by a [(SiH3)(4)AlO4](1) [V-O](1+) cluster model. The catalytic reactivity of these species is compared with that of mononuclear (Fe-O)(1+) sites in ZSM-5 investigated in our earlier work at the same level of theory (J. Catal. 2011, 282, 191). The [V-O](1+) site in ZSM-5 zeolite shows an enhanced catalytic a...
Citation Formats
D. Duzenli, D. O. Atmaca, M. G. Gezer, and I. Önal, “A density functional theory study of partial oxidation of propylene on Cu2O(001) and CuO(001) surfaces,” APPLIED SURFACE SCIENCE, pp. 660–666, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32112.