title: Influence of N-doping on the structure and electronic properties of titania nanoparticle photocatalysts.
abstract: N-containing TiO(2)-based nanostructured materials (average particle size approximately 10 nm) with an anatase-type structure were investigated using oxygen (O) K-edge and titanium (Ti) K- and L-edge X-ray absorption near-edge spectroscopy (XANES). The Ti K pre-edge features indicate that samples predominantly contain ([6])Ti with some ([5])Ti, and there is no evidence for ([4])Ti. We observed that those samples with a larger fraction of Ti in a fivefold coordination, that is, with a significant number of oxygen vacancies, also present a modified Ti environment at the medium-range scale. The presence of these defects drastically modifies the electronic structure of the conduction band, as evidenced by the O K XANES spectra, but does not result in the presence of reduced Ti(3+) states. We discuss the influence of N-doping on titania nanoparticles and their structure, electronics and photocatalytic activity.
authors.affiliation: Departamento de Física, Fac. Ciencias Exactas, Universidad Nacional de La Plata and IFLP (CONICET), C. C. 67 - 1900 La Plata, Argentina.
authors.forename: Silvana J
authors.initials: SJ
authors.lastname: Stewart
authors.forename: Marcos
authors.initials: M
authors.lastname: Fernandez-García
authors.forename: Carolina
authors.initials: C
authors.lastname: Belver
authors.forename: B Simon
authors.initials: BS
authors.lastname: Mun
authors.forename: Félix G
authors.initials: FG
authors.lastname: Requejo