Optical and electrochemical properties of sol-gel spin coated CeO{sub 2}-TiO{sub 2} films

Technical Report · Thu Jun 01 04:00:00 EDT 1995

OSTI ID:251366

Ozer, N; DeSouza, S; Lampert, C M

There are numerous literature reports on the fabrication of CeO{sub 2}-TiO{sub 2} thin films for use in electrochromic applications. As such, CeO{sub 2}-TiO{sub 2} have attracted interest as transparent counter electrodes for smart windows. Here, the optical and electrochemical properties of sol-gel spin coated CeO{sub 2}-TiO{sub 2} (50% CeO{sub 2}) films were investigated for electrochromic applications. The coating solutions were prepared by using mixed organic-inorganic [Ti(OC{sub 2}H{sub 5}){sub 4} and Ce(NH{sub 4}){sub 2} (NO{sub 3}){sub 6}] precursors. X-ray diffraction studies showed the sol-gel spin-coated films were composed of an amorphous matrix of titanium oxide containing nanocrystallites of cerium oxide. The coating solar transmission value was T{sub s} = 0.8 (250 nm thick). The refractive index and the extinction coefficient were derived from transmittance measurements in the UV-VIS-NIR regions. These films had refractive index value of n = 2.18 and extinction coefficient value of k = 8 {times} 10{sup 4} at {lambda} = 550 m. Cyclic voltammetric measurements showed reversible electrochemical insertion of lithium ions in a CeO{sub 2}-TiO{sub 2}/LiClO{sub 4}-propylene carbonate electrochemical cell. During cycling the films maintain high optical transmittance. Spectrophotometric and electrochemical investigations performed on CeO{sub 2}-TiO{sub 2} films revealed that these films are suitable as an optically passive counter-electrode in lithium electrochromic devices.

• Research Organization: Lawrence Berkeley Lab., CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 251366
• Report Number(s): LBL--37390; CONF-9506251--2; ON: DE96011512
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
36 MATERIALS SCIENCE
CERIUM OXIDES
ELECTROCHEMISTRY
ELECTROCHROMISM
EXPERIMENTAL DATA
MICROSTRUCTURE
OPTICAL PROPERTIES
SOL-GEL PROCESS
TITANIUM OXIDES
WINDOWS