| Texto completo | |
| Autor(es): |
Segatelli, Mariana Gava
[1]
;
Radovanovic, Eduardo
[2]
;
Goncalves, Maria do Carmo
[1]
;
Pagotto Yoshida, Inez Valeria
[1]
Número total de Autores: 4
|
| Afiliação do(s) autor(es): | [1] Univ Estadual Campinas, Inst Chem, BR-13083970 Campinas, SP - Brazil
[2] Univ Maringa, Dept Chem, BR-87020900 Maringa, Parana - Brazil
Número total de Afiliações: 2
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of the European Ceramic Society; v. 29, n. 15, p. 3277-3285, DEC 1 2009. |
| Citações Web of Science: | 11 |
| Resumo | |
This study focuses on the structural and morphological changes promoted by heating of silicon oxycarbide ceramics obtained from hybrid polymeric precursors based on poly(methylsiloxane) and divinylbenzene, with or without nickel acetate, by pyrolysis under Ar at different temperatures. The increase of the temperature from 950 to 1500 degrees C promoted the densification and crystallization of SiC and graphite nanodomains in the ceramic bulk with or without Ni, as identified by HRTEM. Moreover, the Ni-containing precursor led to the formation of ultra-long amorphous nanowires on the surface and voids in the ceramic body obtained at 1500 degrees C. These nanowires presented different sizes and morphologies, but similar compositions, basically composed by silicon and oxygen, with the presence of carbon at their external layers. The growth mechanism and the nature of the nanowires are also proposed. The addition of nickel acetate in the polymeric precursor induced the formation of nanowires with different morphologies in the Si-O-C system. (C) 2009 Elsevier Ltd. All rights reserved. (AU) | |
| Processo FAPESP: | 03/09926-1 - Materiais poliméricos e cerâmicos |
| Beneficiário: | Inez Valeria Pagotto Yoshida |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa PRONEX - Temático |
| Processo FAPESP: | 05/58460-0 - Estudos em vidros ceramicos de sicxoy ou sic, enriquecidos com fase dispersa de carbono, obtidos a partir de polimero precursor hibrido. |
| Beneficiário: | Mariana Gava Segatelli |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |