Investigation of catalytic properties and electronic structure of correlated material CeO2 with ab-initio computational methods

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Thesis Type: Postgraduate

Institution Of The Thesis: Orta Doğu Teknik Üniversitesi, Faculty of Arts and Sciences, Department of Physics, Turkey

Approval Date: 2013

Student: BURAK ÖZDEMİR

Supervisor: HANDE TOFFOLİ

Abstract:

Density functional theory employed with Hubbard model addressing strong electronic local correlation source of which considered to be the occupation of d or f type atomic orbitals, since these are localized in space, is used to study ceria (CeO2 ) material. Since ceria exhibits occupied atomic f orbitals on Ce sites and these sites are not equivalent in correlation aspect when surface and defective structures considered, there has been no account of single Hubbard effective U value that captures or improves all the properties. Therefore, locally resolved Hubbard U, by this we mean diff erent U values for every distinct Ce site, is the first approach which should be taken in order to find a method that improves the theoretical accounts of this material and this approach is in the focus of this thesis. Ceria (111) and (110) surfaces, CO and Au adsorptions are investigated with this approach.