| Texto completo | |
| Autor(es): |
Stem, Nair
[1]
;
de Souza, Michele L.
[2]
;
Araujo de Faria, Dalva Lucia
[2]
;
dos Santos Filho, Sebastiao G.
[1]
Número total de Autores: 4
|
| Afiliação do(s) autor(es): | [1] Univ Sao Paulo, Escola Politecn, Lab Sistemas Integraveis, BR-05508900 Sao Paulo - Brazil
[2] Univ Sao Paulo, Inst Quim, LEM, BR-05508900 Sao Paulo - Brazil
Número total de Afiliações: 2
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Thin Solid Films; v. 558, p. 67-74, MAY 2 2014. |
| Citações Web of Science: | 9 |
| Resumo | |
In this work, it is investigated the formation of Ti(III) and Ti(IV) states at the surface and in the bulk of the Ti3O5 material grown as meshes of nano-and micro-fibers obtained from hydrothermal annealing of C-doped TiO2 on Si. The topography and distribution of the fibers in the meshes were characterized by atomic force microscopy. When the fiber distribution was more compact, a higher photoluminescence signal at 850 nm (1.46 eV) was obtained, indicating the presence of a higher number of defects corresponding to the Ti(III) sites. From X-ray photoelectron spectroscopy, it was obtained a Ti(III)/Ti(IV) ratio much lower than the expected value for the Ti3O5 phase (2 Ti(III): 1 Ti(IV)). The discrepancy was mainly attributed to the reaction of surface Ti(III) states of the Ti3O5 fibers with water during the hydrothermal annealing, resulting in surface Ti(IV) with - OH radicals. On the other hand, X-ray photoelectron spectroscopy also indicated that substitutional and interstitial carbon atoms coexist, elemental carbon exists in the samples due to the co-deposition process and, as a result, the carbon inside of the TiO2 rutile lattice is acting as one of the precursors for the formation of Ti3O5. (C) 2014 Elsevier B.V. All rights reserved. (AU) | |
| Processo FAPESP: | 08/03636-5 - Nanocompósitos metálicos para aplicações em processos fotoquímicos intensificados: efeitos de plasmon em fotocatálise e fotoeletroquímica |
| Beneficiário: | Michele Lemos de Souza |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado Direto |
| Processo FAPESP: | 06/58748-7 - Reatividade, dinâmica e espectroscopia de sistemas complexos |
| Beneficiário: | Marcia Laudelina Arruda Temperini |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |