Adsorption of water on porous Vycor glass studied by ellipsometry

The variation of the optical properties of porous Vycor glass (Corning, Model 7930) under different relative-humidity conditions was studied. The adsorption of water into the glass pores was investigated with spectroscopic ellipsometry. The change of the refractive index was Δn ∼ 0.04 between 5% and...

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Detalles Bibliográficos
Autores: Álvarez Herrero, Alberto, López Heredero, Raquel, Levy, David, Bernabeu Martínez, Eusebio
Tipo de recurso: artículo
Fecha de publicación:2001
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/59227
Acceso en línea:https://hdl.handle.net/20.500.14352/59227
Access Level:acceso abierto
Palabra clave:535
Neutron-Scattering
Surface
Layers
Gases
Óptica (Física)
2209.19 Óptica Física
Descripción
Sumario:The variation of the optical properties of porous Vycor glass (Corning, Model 7930) under different relative-humidity conditions was studied. The adsorption of water into the glass pores was investigated with spectroscopic ellipsometry. The change of the refractive index was Δn ∼ 0.04 between 5% and 90% relative humidity. A linear relation between the ellipsometer parameter tan Ψ, the amount of water adsorbed in the glass pores, and information about the pore-size distributions was established. The results are in accord with the values obtained from N2 isotherms, transmission electron microscope micrographs, and the manufacturer’s specifications (radius of ∼20 Å). The possibility of using this material as a transducer for implementation in a fiber-optic sensor to measure humidity was evaluated.