Thin film of CeO2-SiO2: a new ion storage layer for smart windows

• Published in: Solar energy materials and solar cells 2003-12, Vol.80 (4), p.443-449
• Main Authors: BERTON, Marcos A. C, AVELLANEDA, César O, BULHOES, Luis O. S
• Format: Article
• Language: English
• Subjects: Applied sciences; Buildings; Buildings. Public works; Energy; Exact sciences and technology; External envelopes; Miscellaneous; Natural energy; Opening. Closure. Circulation (stairs, etc.); Solar energy
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2003.08.012

Thin solid films of CeO2-SiO2 used as a counter-electrode layer in electrochromic devices, were prepared by the sol-gel dip coating, using an aqueous-based process. The influence of the SiO2 addition on electrochemistry of the CeO2 oxide coatings was determined by chronoamperometric measurements. The films exhibit a larger charge storage capacity, which was determined as a function of the coatings thickness. The peak occurrence in the chronoamperometric curve during the deintercalation of lithium ions in the cerium/silicon films is analyzed in terms of trapping energy levels for Li ions into the film. In situ UV-Vis spectroelectrochemical measurements of the CeO2-SiO2 coatings indicated that the films remained transparent in the visible spectral range during the intercalation process. Powders were characterized by X-ray diffraction after the same thermal treatment of the films, indicating a decrease of crystallinity with the doping. The feasibility for use of these electrodes as ion storage for electrochromic devices was investigated.