SEM and Raman study of thermally treated TiO2 anatase nanopowders: Influence of calcination on photocatalytic activity

N. Mahdjoub, N. Allen, P. Kelly, V. Vishnyakov

Research output: Contribution to journalArticle

35 Citations (Scopus)

Abstract

Titania (TiO2) nanopowders called PC 500, synthesised by the sulphate process, were annealed in air at temperatures of up to 1022K for 30min. The X-ray Diffraction (XRD) indicates that the thermal annealing resulted in coarsening of the average crystallite size from 13 to 72nm. However, Scanning Electron Microscopy (SEM) reveals persistence of platelet-like structures which survive up to temperatures around 900K. This implies that the crystals at least partially grow within the plates in 2D confinement. This implies that direct usage of Scherrer equation in this case should be approached with care. Raman spectra peak positions and the Full-Width-at-Half-Maximum (FWHM) values changed considerably after calcinations crystal growth, while, material composition and oxygen content remain unchanged. The Raman peak behaviour can be cautiously attributed to the first order phonon confinement phenomena, but both, 2D and 3D models of confinement should be accounted. The highest photoactivity, as indicated by photoinduced degradation of a mono azo dye methyl-orange (C14H14N3SO3Na), was observed in material treated at 773K.

LanguageEnglish
Pages59-64
Number of pages6
JournalJournal of Photochemistry and Photobiology A: Chemistry
Volume211
Issue number1
Early online date16 Feb 2010
DOIs
Publication statusPublished - 5 Mar 2010
Externally publishedYes

Fingerprint

anatase
Calcination
roasting
Titanium dioxide
Azo Compounds
Scanning electron microscopy
scanning electron microscopy
Azo dyes
Coarsening
Crystallite size
Platelets
Crystallization
Full width at half maximum
Crystal growth
Sulfates
Titania
Raman scattering
Titanium
Annealing
Oxygen

Cite this

@article{df76236322de4373abff7ffc8e660375,
title = "SEM and Raman study of thermally treated TiO2 anatase nanopowders: Influence of calcination on photocatalytic activity",
abstract = "Titania (TiO2) nanopowders called PC 500, synthesised by the sulphate process, were annealed in air at temperatures of up to 1022K for 30min. The X-ray Diffraction (XRD) indicates that the thermal annealing resulted in coarsening of the average crystallite size from 13 to 72nm. However, Scanning Electron Microscopy (SEM) reveals persistence of platelet-like structures which survive up to temperatures around 900K. This implies that the crystals at least partially grow within the plates in 2D confinement. This implies that direct usage of Scherrer equation in this case should be approached with care. Raman spectra peak positions and the Full-Width-at-Half-Maximum (FWHM) values changed considerably after calcinations crystal growth, while, material composition and oxygen content remain unchanged. The Raman peak behaviour can be cautiously attributed to the first order phonon confinement phenomena, but both, 2D and 3D models of confinement should be accounted. The highest photoactivity, as indicated by photoinduced degradation of a mono azo dye methyl-orange (C14H14N3SO3Na), was observed in material treated at 773K.",
keywords = "Calcination, Dye fading, Photocatalysis, Raman, Titanium dioxide",
author = "N. Mahdjoub and N. Allen and P. Kelly and V. Vishnyakov",
year = "2010",
month = "3",
day = "5",
doi = "10.1016/j.jphotochem.2010.02.002",
language = "English",
volume = "211",
pages = "59--64",
journal = "Journal of Photochemistry and Photobiology A: Chemistry",
issn = "1010-6030",
publisher = "Elsevier",
number = "1",

}

SEM and Raman study of thermally treated TiO2 anatase nanopowders : Influence of calcination on photocatalytic activity. / Mahdjoub, N.; Allen, N.; Kelly, P.; Vishnyakov, V.

In: Journal of Photochemistry and Photobiology A: Chemistry, Vol. 211, No. 1, 05.03.2010, p. 59-64.

Research output: Contribution to journalArticle

TY - JOUR

T1 - SEM and Raman study of thermally treated TiO2 anatase nanopowders

T2 - Journal of Photochemistry and Photobiology A: Chemistry

AU - Mahdjoub, N.

AU - Allen, N.

AU - Kelly, P.

AU - Vishnyakov, V.

PY - 2010/3/5

Y1 - 2010/3/5

N2 - Titania (TiO2) nanopowders called PC 500, synthesised by the sulphate process, were annealed in air at temperatures of up to 1022K for 30min. The X-ray Diffraction (XRD) indicates that the thermal annealing resulted in coarsening of the average crystallite size from 13 to 72nm. However, Scanning Electron Microscopy (SEM) reveals persistence of platelet-like structures which survive up to temperatures around 900K. This implies that the crystals at least partially grow within the plates in 2D confinement. This implies that direct usage of Scherrer equation in this case should be approached with care. Raman spectra peak positions and the Full-Width-at-Half-Maximum (FWHM) values changed considerably after calcinations crystal growth, while, material composition and oxygen content remain unchanged. The Raman peak behaviour can be cautiously attributed to the first order phonon confinement phenomena, but both, 2D and 3D models of confinement should be accounted. The highest photoactivity, as indicated by photoinduced degradation of a mono azo dye methyl-orange (C14H14N3SO3Na), was observed in material treated at 773K.

AB - Titania (TiO2) nanopowders called PC 500, synthesised by the sulphate process, were annealed in air at temperatures of up to 1022K for 30min. The X-ray Diffraction (XRD) indicates that the thermal annealing resulted in coarsening of the average crystallite size from 13 to 72nm. However, Scanning Electron Microscopy (SEM) reveals persistence of platelet-like structures which survive up to temperatures around 900K. This implies that the crystals at least partially grow within the plates in 2D confinement. This implies that direct usage of Scherrer equation in this case should be approached with care. Raman spectra peak positions and the Full-Width-at-Half-Maximum (FWHM) values changed considerably after calcinations crystal growth, while, material composition and oxygen content remain unchanged. The Raman peak behaviour can be cautiously attributed to the first order phonon confinement phenomena, but both, 2D and 3D models of confinement should be accounted. The highest photoactivity, as indicated by photoinduced degradation of a mono azo dye methyl-orange (C14H14N3SO3Na), was observed in material treated at 773K.

KW - Calcination

KW - Dye fading

KW - Photocatalysis

KW - Raman

KW - Titanium dioxide

UR - http://www.scopus.com/inward/record.url?scp=77950460362&partnerID=8YFLogxK

U2 - 10.1016/j.jphotochem.2010.02.002

DO - 10.1016/j.jphotochem.2010.02.002

M3 - Article

VL - 211

SP - 59

EP - 64

JO - Journal of Photochemistry and Photobiology A: Chemistry

JF - Journal of Photochemistry and Photobiology A: Chemistry

SN - 1010-6030

IS - 1

ER -