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Title: Size and Shape Control of Nanocrystallites in Mesoporous TiO2 Films

Abstract

No abstract prepared.

Authors:
;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
915659
DOE Contract Number:
AC36-99-GO10337
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Materials Chemistry; Journal Volume: 17; Journal Issue: 2007
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; SHAPE; TITANIUM OXIDES; FILMS; Basic Sciences

Citation Formats

Neale, N. R., and Frank, A. J. Size and Shape Control of Nanocrystallites in Mesoporous TiO2 Films. United States: N. p., 2007. Web. doi:10.1039/b700885f.
Neale, N. R., & Frank, A. J. Size and Shape Control of Nanocrystallites in Mesoporous TiO2 Films. United States. doi:10.1039/b700885f.
Neale, N. R., and Frank, A. J. Mon . "Size and Shape Control of Nanocrystallites in Mesoporous TiO2 Films". United States. doi:10.1039/b700885f.
@article{osti_915659,
title = {Size and Shape Control of Nanocrystallites in Mesoporous TiO2 Films},
author = {Neale, N. R. and Frank, A. J.},
abstractNote = {No abstract prepared.},
doi = {10.1039/b700885f},
journal = {Journal of Materials Chemistry},
number = 2007,
volume = 17,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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  • Introducing mesoscale pores into spincoated titanium dioxide films, prepared by spincoating different sol-gel precursor solutions on silicon substrates and subsequent annealing at 350 C, 400 C or 450 C, respectively, affects several optical properties of the material. The change in refractive index observed for different mesoporous anatase films directly correlates with changes in pore size, but is also in a more complex manner influenced by the film thickness and the density of pores within the films. Additionally, the band gap of the films is blueshifted by the stress the introduction of pores exerts on the inorganic matrix. The differently sizedmore » pores were templated by Pluronic{reg_sign} block copolymers in the solgel solutions and tuned by employing different annealing temperatures for the film preparation. This study focused on elucidating the effect different templating materials (F127 and P123) have on the pore size of the final mesoporous titania film, and on understanding the relation of varying polymer concentration (taking P123 as an example) in the sol-gel solution to the pore concentration and size in the resultant titania film. Titania thin film samples or corresponding titanium dioxide powders were characterized by X-ray diffraction, nitrogen adsorption, ellipsometery, UV/Vis spectrometry and other techniques to understand the interplay between mesoporosity and optical properties.« less
  • Mesoporous TiO2 thin films were synthesized by sol-gel processing using an aqueous-based, inexpensive and environmentally friendly precursor and cationic surfactants as templates under mild reaction conditions. The films were prepared by spin-coating on glass substrates followed by calcination to remove the surfactant. N2 sorption, x-ray diffraction and TEM were used to characterize the porosity, pore size and pore structure before and after calcination. Films were found to have wormlike pore structures after calcination, and surface areas on the order of 200 m2/g. These results show that the mesostructure and porosity of the thin films can be controlled by the surfactantmore » template chemistry such as surfactant/Ti ratio, pH, and the rate of solvent evaporation.« less