Dissociative adsorption of methane on the Cu and Zn doped (111) surface of CeO2


Autoria(s): Carey, John J.; Nolan, Michael
Data(s)

20/10/2016

20/10/2016

04/04/2016

Resumo

The development of economical heterogeneous catalysts for the activation of methane is a major challenge for the chemical industry. Screening potential candidates becomes more feasible using rational catalyst design to understand the activity of potential catalysts for CH4 activation. The focus of the present paper is the use of density functional theory to examine and elucidate the properties of doped CeO2. We dope with Cu and Zn transition metals having variable oxidation state (Cu), and a single oxidation state (Zn), and study the activation of methane. Zn is a divalent dopant and Cu can have a +1 or +2 oxidation state. Both Cu and Zn dopants have an oxidation state of +2 after incorporation into the CeO2 (111) surface; however a Hubbard +U correction (+U = 7) on the Cu 3d states is required to maintain this oxidation state when the surface interacts with adsorbed species. Dissociation of methane is found to occur locally at the dopant cations, and is thermodynamically and kinetically more favorable on Zn-doped CeO2 than Cu-doped CeO2. The origins of this lie with the Zn(II) dopant moving towards a square pyramidal geometry in the sub surface layer which facilitates the formation of two-coordinated surface oxygen atoms, that are more beneficial for methane activation on a reducible oxide surface. These findings can aid in rational experimental catalyst design for further exploration in methane activation processes.

Formato

application/pdf

Identificador

Carey, J. J. and Nolan, M. (2016) ‘Dissociative adsorption of methane on the Cu and Zn doped (111) surface of CeO2’, Applied Catalysis B: Environmental, 197, pp. 324-336. doi: 10.1016/j.apcatb.2016.04.004

197

324

336

0926-3373

http://hdl.handle.net/10468/3199

10.1016/j.apcatb.2016.04.004

Applied Catalysis B: Environmental

Idioma(s)

en

Publicador

Elsevier

Relação

info:eu-repo/grantAgreement/EC/FP7::SP1::NMP/604296/EU/Catalytic Partial Oxidation of Bio Gas and Reforming of Pyrolysis Oil (Bio Oil) for an Autothermal Synthesis Gas Production and Conversion into Fuels/BIOGO-FOR-PRODUCTION

info:eu-repo/grantAgreement/EC/FP7::SP1::NMP/604296/EU/Catalytic Partial Oxidation of Bio Gas and Reforming of Pyrolysis Oil (Bio Oil) for an Autothermal Synthesis Gas Production and Conversion into Fuels/BIOGO-FOR-PRODUCTION

Direitos

© 2016, Elsevier B.V. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/

https://creativecommons.org/licenses/by-nc-nd/4.0/

Palavras-Chave #Methane activation #Density functional theory #CeO2 #Transition metal doping
Tipo

Article (peer-reviewed)