Photodegradation of methylene blue using crystalline titanosilicate quantum-confined semiconductor

Autores
Luca, Vittorio; Osborne, Michael; Sizgek, Devlet; Griffith, Christopher; Araujo, Paula Zulema
Año de publicación
2006
Idioma
inglés
Tipo de recurso
artículo
Estado
Versión publicada
Descripción
Synthetic sitinakite contains in its structure a discrete wire-like sublattice of linked TiO6 octahedra. This sublattice is held apart by silicate tetrahedra forming one-dimensional channels that run down the c axis. The optical properties of this structural arrangement have been studied and compared with other titanosilicate phases, the best known being ETS-10. Thus, sitinakite which has twice the titanate wire diameter of ETS-10 has a band gap of 4.07 eV compared with 3.87 eV. The reduced electron-hole effective mass of the sitinakite quantum-confined system has been calculated through use of the effective mass model and compared with that of other titanosilicate materials. The sitinakite phase has been shown to effectively photodegrade methylene blue (MB) dye at pH 7 using visible light excitation and displays a higher degradation rate than TiO2 (Degussa, P25) under the same experimental conditions. On the contrary, under UV excitation, the photodegradation rate obtained using P25 is much higher than that using sitinakite. Given that the band edge of sitinkaite is significantly blue shifted compared with that of P25, photodegradation of MB using sitinakite is attributed to sensitization of the MB cationic dye which is strongly adsorbed onto the negatively charged sitinakite surfaces.
Fil: Luca, Vittorio. Australian Nuclear Science and Technology Organisation; Australia
Fil: Osborne, Michael. Australian Nuclear Science and Technology Organisation; Australia
Fil: Sizgek, Devlet. Australian Nuclear Science and Technology Organisation; Australia
Fil: Griffith, Christopher. Australian Nuclear Science and Technology Organisation; Australia
Fil: Araujo, Paula Zulema. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Materia
X-RAY ABSORPTION
TITANIUM OXIDE
PHOTOCATALYSIS
ION-EXCHANGE
TITOSILICATE
Otras Ciencias Químicas
Ciencias Químicas
CIENCIAS NATURALES Y EXACTAS
Nivel de accesibilidad
Acceso restringido
Licencia
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/54100