Share Email Print

Proceedings Paper

Nanostructured TiO2 semiconductor electrodes modified with surface-attached viologens: applications for displays and smart windows
Author(s): Anders Hagfeldt; Lorenz Walder; Michael Graetzel
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Viologen derivatives adsorbed on TiO2 surfaces in nanocrystalline-nanoporous electrodes have been studied with respect to electrochromic phenomena. The transparent nature and the high internal surface area of these electrodes are very beneficial for this purpose. Two different viologens were studied giving rise to blue, green, and violet coloration. For one of the viologens we show the possibility to vary the color for the same viologen/TiO2 electrode from transparent to green or violet depending on the applied potential. Depending on the applied potential different optical densities were obtained. Optical density changes from 0.1 up to 1 and coloration efficiencies above 100 cm2C-1, with a maximum value of 440 cm2C-1, were obtained. The switching times for these electrodes for both coloration and bleaching were faster than 1s for a transmittance change larger than 60%, using 0.5M LiClO4 in acetonitrile as electrolyte. Preliminary stability tests were performed. One electrode has been cycled 654 times without substantial decline in coloration efficiency.

Paper Details

Date Published: 23 August 1995
PDF: 10 pages
Proc. SPIE 2531, Optical Materials Technology for Energy Efficiency and Solar Energy Conversion XIV, (23 August 1995); doi: 10.1117/12.217359
Show Author Affiliations
Anders Hagfeldt, Swiss Federal Institute of Technology (Switzerland)
Lorenz Walder, Swiss Federal Institute of Technology (Switzerland)
Michael Graetzel, Swiss Federal Institute of Technology (Switzerland)

Published in SPIE Proceedings Vol. 2531:
Optical Materials Technology for Energy Efficiency and Solar Energy Conversion XIV
Carl M. Lampert; Satyen K. Deb; Claes-Goeran Granqvist, Editor(s)

© SPIE. Terms of Use
Back to Top