Aerosol-assisted production of mesoporous titania microspheres with enhanced photocatalytic activity: the basis of an improved process.
ACS Appl Mater Interfaces
; 2(6): 1663-73, 2010 Jun.
Article
em En
| MEDLINE
| ID: mdl-20527733
An aerosol-based process was used to prepare mesoporous TiO(2) microspheres (MTM) with an average diameter in the range of 0.5-1 microm. The structural characteristics and photocatalytic properties of the synthesized materials were determined. As-prepared MTM materials and those heated in air from 400 to 600 degrees C exhibited mesoporous texture with a narrow size distribution and an inorganic framework that consisted of 4-13 nm anatase crystallites. Pore volumes for the MTM materials were in the range of 0.17-0.34 cm(3) g(-1). Microspheres heated to 400 degrees C presented a locally ordered mesopore structure and possessed X-ray diffraction d spacings between 9.8 and 17.3 nm. Heating above 400 degrees C resulted in a loss of the mesoscopic order, a decrease of the surface area, retention of the porosity, and an increase of the anatase nanoparticle size to 13 nm. The accessibility of the pore volume was measured by monitoring the uptake of gallic acid (GA) using Fourier transform IR. The MTM materials made excellent catalysts for the photodegradation of GA, with the performance being higher than that of an equivalent sample of Degussa P25. The present MTM materials are advantageous in terms of their ease of separation from the aqueous phase, and hence a novel photocatalytic process is proposed based on separate adsorption and photocatalytic decomposition steps with an improved and more rational use of both catalyst and sunlight.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fotoquímica
/
Titânio
/
Aerossóis
/
Microesferas
Idioma:
En
Revista:
ACS Appl Mater Interfaces
Assunto da revista:
BIOTECNOLOGIA
/
ENGENHARIA BIOMEDICA
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Argentina
País de publicação:
Estados Unidos