| Texto completo | |
| Autor(es): |
da Silva, Luis F.
;
M'Peko, Jean-Claude
;
Andres, Juan
;
Beltran, Armando
;
Gracia, Lourdes
;
Bernardi, Maria I. B.
;
Mesquita, Alexandre
;
Antonelli, Eduardo
;
Moreira, Mario L.
;
Mastelaro, Valmor R.
Número total de Autores: 10
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of Physical Chemistry C; v. 118, n. 9, p. 11-pg., 2014-03-06. |
| Resumo | |
This paper reports an experimental and theoretical investigation of the effects of adding Fe to the perovskite strontium titanate SrTiO3. The effects include changes in the short-order range structure as well as in the electronic and electrical properties. X-ray diffraction analysis reveals that the SrTi1-xFexO3 network shrinks with increasing Fe content, while X-ray absorption spectroscopy measurements of the Ti and Fe K-edge revealed the presence of some under-coordinated TiO5 units created because of the partial replacement of Fe3+ ions in the Ti4+. site. UV-visible absorption spectra indicated a reduction in optical gap with increasing Fe content. The electronic structure and spin densities of STFO with x = 0, 0.0625, 0.125, 0.5, and 1 are calculated by the OFT method at the B3LYP computational level, showing a Jahn-Teller distortion of O atoms surrounding the Fe as well as the formation of under-coordinated TiO5 units. From the electrical viewpoint, the results show that STFO is a mixed (ionic and electronic) conductor and that the electronic contribution becomes dominant with increasing Fe content. (AU) | |
| Processo FAPESP: | 13/09573-3 - Síntese e Caracterização de Heteroestruturas de ZnO/SnO2 obtidas pelo Método Hidrotermal: Aplicação como Sensores de Gás |
| Beneficiário: | Luís Fernando da Silva |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |