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Electron energy-loss study of titania particles

Published online by Cambridge University Press:  31 January 2011

R. J. Gonzalez  and
A. L. Ritter
R. J. Gonzalez
Affiliation:
Department of Physics, Virginia Tech, Blacksburg, Virginia 24061
A. L. Ritter
Affiliation:
Department of Physics, Virginia Tech, Blacksburg, Virginia 24061
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Abstract

Small titania particles, prepared by hydrolysis and condensation using in situ steric stabilization, have been studied by high-energy, transmission, electron energy-loss spectroscopy. Electron diffraction patterns and energy-loss spectra as a function of momentum transfer were measured for as-prepared particles (amorphous titania), particles annealed at 600 °C (primarily anatase), and particles annealed at 1000 °C (primarily rutile). The energy-loss spectra at low momentum disagreed with the loss function calculated from optical data (rutile) and disagreed with theory (rutile and anatase). The data was fit by an Elliot-like model for a resonant exciton interacting with a continuum of levels. The translational effective mass of the exciton derived from the fitting was quite large, indicating that it was self-trapped.

Type
Articles
Information
Journal of Materials Research , Volume 13 , Issue 6 , June 1998 , pp. 1679 - 1687
Copyright
Copyright © Materials Research Society 1998

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