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Title: Flexible solid-state photoelectrochromic windows

Abstract

Photoelectrochromic smart window technology is extended to include the use of flexible substrates and solid-state electrolytes. This should facilitate their application as retrofit modifications of office windows, where, by blocking incoming solar irradiation, they could substantially lower air-conditioning costs. These devices are based on a dye-sensitized TiO{sub 2} electrode coupled with a 500 nm thick WO{sub 3} electrochromic counter electrode, separated by a cross-linked polymer electrolyte containing LiI. A novel method for preparing conducting nanoporous TiO{sub 2} films is described that allows for the construction of these devices on flexible organic substrates. Colloidal solutions of TiO{sub 2} free of surfactants were spin-coated onto indium-tin oxide coated polyester substrates, resulting in highly transparent films ranging from 100 nm to 1 {micro}m in thickness. Upon annealing at 100 C, these films were strongly adherent and displayed excellent photoconductivity as shown by their current-voltage characteristics. The devices typically transmit 75% of visible light in the bleached state. After a few minutes of exposure to white light (75 mW/cm{sup 2}), the windows turn dark blue, transmitting only 30% of visible light. They spontaneously bleach back to their initial noncolored state upon removal of the light source.

Authors:
; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab., Golden, CO (US)
Sponsoring Org.:
USDOE
OSTI Identifier:
20003952
Resource Type:
Journal Article
Journal Name:
Journal of the Electrochemical Society
Additional Journal Information:
Journal Volume: 146; Journal Issue: 11; Other Information: PBD: Nov 1999; Journal ID: ISSN 0013-4651
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; 36 MATERIALS SCIENCE; PHOTOCHROMIC MATERIALS; ELECTROCHROMISM; WINDOWS; FLEXIBILITY; TITANIUM OXIDES; TUNGSTEN OXIDES

Citation Formats

Pichot, F, Ferrere, S, Pitts, R J, and Gregg, B A. Flexible solid-state photoelectrochromic windows. United States: N. p., 1999. Web. doi:10.1149/1.1392635.
Pichot, F, Ferrere, S, Pitts, R J, & Gregg, B A. Flexible solid-state photoelectrochromic windows. United States. https://doi.org/10.1149/1.1392635
Pichot, F, Ferrere, S, Pitts, R J, and Gregg, B A. 1999. "Flexible solid-state photoelectrochromic windows". United States. https://doi.org/10.1149/1.1392635.
@article{osti_20003952,
title = {Flexible solid-state photoelectrochromic windows},
author = {Pichot, F and Ferrere, S and Pitts, R J and Gregg, B A},
abstractNote = {Photoelectrochromic smart window technology is extended to include the use of flexible substrates and solid-state electrolytes. This should facilitate their application as retrofit modifications of office windows, where, by blocking incoming solar irradiation, they could substantially lower air-conditioning costs. These devices are based on a dye-sensitized TiO{sub 2} electrode coupled with a 500 nm thick WO{sub 3} electrochromic counter electrode, separated by a cross-linked polymer electrolyte containing LiI. A novel method for preparing conducting nanoporous TiO{sub 2} films is described that allows for the construction of these devices on flexible organic substrates. Colloidal solutions of TiO{sub 2} free of surfactants were spin-coated onto indium-tin oxide coated polyester substrates, resulting in highly transparent films ranging from 100 nm to 1 {micro}m in thickness. Upon annealing at 100 C, these films were strongly adherent and displayed excellent photoconductivity as shown by their current-voltage characteristics. The devices typically transmit 75% of visible light in the bleached state. After a few minutes of exposure to white light (75 mW/cm{sup 2}), the windows turn dark blue, transmitting only 30% of visible light. They spontaneously bleach back to their initial noncolored state upon removal of the light source.},
doi = {10.1149/1.1392635},
url = {https://www.osti.gov/biblio/20003952}, journal = {Journal of the Electrochemical Society},
issn = {0013-4651},
number = 11,
volume = 146,
place = {United States},
year = {Mon Nov 01 00:00:00 EST 1999},
month = {Mon Nov 01 00:00:00 EST 1999}
}