Tungsten Oxide Electrochromic Windows with Lithium Polymer Electrolytes

• Type: Article in International Scientific Journal
• Date: 2010

Authors

Sequeira, CAC (Author) Other

Journal

Title: Journal of the Electrochemical Society

Vol. 157 No. 5

Pages: J202-J207

ISSN: 0013-4651

Publisher: Electrochemical Society, Inc.

Indexing

ISI Web of Knowledge - 9 Citations

Scopus - 10 Citations

Other information

Authenticus ID: P-003-BSB

DOI: 10.1149/1.3364865

Abstract (EN): Electrochromic windows are built using WO(3) as the electrochromic material and V(2)O(5) as the counter electrode. Both are deposited onto indium tin oxide coated glass panes by vacuum evaporation and are amorphous to X-ray diffraction. The electrolytes are lithium conducting polymers constituted by lithium-N,N-diallylamide-1-tetrafluoroethane sulfonate grafted in a cross-linked polyether network poly(isobutenyloligooxyethylene), with t(Li+) close to unity, and poly(ethylene glycol)-borate ester with LiCF(3)SO(3), with t(Li+) close to 0.34. The electrochemical characterization of the electrodes is carried out by cyclic voltammetry, coulometric titration, and impedance spectroscopy, allowing the determination of the chemical diffusion coefficients of lithium into WO(3) and V(2)O(5). Potentiostatic cycling of the complete transmissive cells yield a transmission variation from 48 to 12% at similar to 630 nm with a response time of 10 s at room temperature. The main drawbacks are the residual coloration in the bleached state and the low exchange current densities at room temperature, which underline the need for good electrolyte/electrode contacts.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6