Publicação: XPS study on water corrosion of fluorzirconate glasses and their protection by a layer of surface modified tin dioxide nanoparticles
Nenhuma Miniatura disponível
Data
2007-05-01
Orientador
Coorientador
Pós-graduação
Curso de graduação
Título da Revista
ISSN da Revista
Título de Volume
Editor
Elsevier B.V.
Tipo
Artigo
Direito de acesso
Acesso restrito
Resumo
The surface corrosion process associated with the hydrolysis of fluorozirconate glass, Z-BLAN (53ZrF(4), 20BaF(2), 20NaF, 4LaF(2), 3AlF(3)), and the corrosion protection efficiency of a nanocrystalline transparent SnO2 layer were investigated by X-ray photoelectron spectroscopy. The tin oxide film was deposited by the sol-gel dip-coating process in the presence of Tiron(R) as particle surface modifier agent. The chemical bonding structure and composition of the surface region of coated and non-coated ZBLAN were studied before water contact and after different immersion periods (5-30 min). In contrast to the effects occurring for non-coated glass, where the surface undergoes a rapid selective dissolution of the most soluble species inducing the formation of a new surface phase consisting of stable zirconium oxyfluoride, barium fluoride and lanthanum fluoride species, the results for the SnO2-coated glass showed that the hydrolytic attack induces a filling of the film nanopores by dissolved glass material and the formation of tin oxylluoride and zirconium oxyfluoride species. This process results in a modified film, which acts as a hermetic diffusion barrier protecting efficiently the glass surface. (C) 2006 Elsevier B.V. All rights reserved.
Descrição
Idioma
Inglês
Como citar
Journal of Electron Spectroscopy and Related Phenomena. Amsterdam: Elsevier B.V., v. 156, p. 128-134, 2007.
