Effect of calcination atmosphere on TiO2 photocatalysis in hydrogen production from methanol/water solution
Journal
Journal of Photochemistry and Photobiology A: Chemistry
Journal Volume
163
Journal Issue
1-2
Pages
277-280
Date Issued
2004
Author(s)
Abstract
TiO2 photocatalysts were synthesized by a sol-gel process followed by calcination at 400 °C in Ar, air, N2, H2 (3% in N2) and vacuum (∼5×10-3 torr), respectively. Toward H2 production from a water/methanol (vol. ratio=1.4/1) solution, the catalysts exhibited activities in the order, according to calcination atmosphere, of Ar>air>N2>vacuum∼H2. The low activity resulting from either vacuum or H2 calcination was ascribed to a reduced coverage of surface hydroxyl and high bulk defect density, based on the X-ray photoelectron and UV-Vis spectroscopic analyses, while the high activity from Ar calcination is to enhanced visible-light excitation. © 2004 Elsevier B.V. All rights reserved.
Subjects
Calcination atmosphere; Hydrogen production; Methanol; Phototcatalysis; TiO2; X-ray photoelectron spectroscopy
Other Subjects
argon; hydrogen; hydroxyl group; methanol; nitrogen; titanium dioxide; water; air; article; atmosphere; catalyst; chemical procedures; controlled study; gel; light; photocatalysis; solid; surface property; synthesis; temperature; ultraviolet spectroscopy; vacuum; X ray photoelectron spectroscopy
Type
journal article