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Title: Enhanced Optical Absorption Induced by Dense Nanocavities Inside Titania Nanorods

Abstract

Titania, a wide band gap semiconductor, can generate powerful oxidants and reductants by absorbing photon energies. Titania has been extensively used in photoelectrochemical systems, such as dye-sensitized titania, a wide band gap semiconductor, can generate powerful oxidants and reductants by absorbing photon energies. To improve the photoreactivity of titania, several approaches, including doping and metal loading have been proposed. Nanocavities are isolated entities inside a solid and hence are very different from nanoporous, whose pores (often amorphous and irregular) connect together and open to the surface. Dense polyhedral nanocavities inside single-crystalline anatase titania nanorods were successfully synthesized by simply heating titanate nanorods. The size of the nanocavities is typically about 10 nm. The surfaces of the nanocavity polyhedron are determined to be the crystallographic low-index planes of the titania crystal. We found that these dense nanocavities significantly enhance the optical absorption coefficient of titania in the near-ultraviolet region, thereby providing a new approach to increasing the photoreactivity of the titania nanorods in the applications related to absorbing photons.

Authors:
; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
929978
Report Number(s):
BNL-80585-2008-JA
TRN: US200822%%1136
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Advanced Materials; Journal Volume: 19; Journal Issue: 18
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION; AUGMENTATION; HEATING; LOADING; METALS; OXIDIZERS; PHOTONS; SEMICONDUCTOR MATERIALS; SIZE; SOLIDS; SURFACES; TITANATES; national synchrotron light source

Citation Formats

Han,W., Wu, L., Klie, R., and Zhu, Y.. Enhanced Optical Absorption Induced by Dense Nanocavities Inside Titania Nanorods. United States: N. p., 2007. Web. doi:10.1002/adma.200700540.
Han,W., Wu, L., Klie, R., & Zhu, Y.. Enhanced Optical Absorption Induced by Dense Nanocavities Inside Titania Nanorods. United States. doi:10.1002/adma.200700540.
Han,W., Wu, L., Klie, R., and Zhu, Y.. Mon . "Enhanced Optical Absorption Induced by Dense Nanocavities Inside Titania Nanorods". United States. doi:10.1002/adma.200700540.
@article{osti_929978,
title = {Enhanced Optical Absorption Induced by Dense Nanocavities Inside Titania Nanorods},
author = {Han,W. and Wu, L. and Klie, R. and Zhu, Y.},
abstractNote = {Titania, a wide band gap semiconductor, can generate powerful oxidants and reductants by absorbing photon energies. Titania has been extensively used in photoelectrochemical systems, such as dye-sensitized titania, a wide band gap semiconductor, can generate powerful oxidants and reductants by absorbing photon energies. To improve the photoreactivity of titania, several approaches, including doping and metal loading have been proposed. Nanocavities are isolated entities inside a solid and hence are very different from nanoporous, whose pores (often amorphous and irregular) connect together and open to the surface. Dense polyhedral nanocavities inside single-crystalline anatase titania nanorods were successfully synthesized by simply heating titanate nanorods. The size of the nanocavities is typically about 10 nm. The surfaces of the nanocavity polyhedron are determined to be the crystallographic low-index planes of the titania crystal. We found that these dense nanocavities significantly enhance the optical absorption coefficient of titania in the near-ultraviolet region, thereby providing a new approach to increasing the photoreactivity of the titania nanorods in the applications related to absorbing photons.},
doi = {10.1002/adma.200700540},
journal = {Advanced Materials},
number = 18,
volume = 19,
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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