@conference {1855,
	title = {Structural and Optical Properties of Sol-Gel Deposited Proton Conducting Ta<sub>2</sub>O<sub>5</sub> Films},
	booktitle = {8th International Workshop on Glasses and Ceramics From Gels},
	year = {1995},
	month = {09/1995},
	address = {Faro, Portugal},
	abstract = {<p>Proton conducting tantalum oxide films were deposited by spin coating using a sol-gel process. The coating solutions were prepared using Ta(OC<sub>2</sub>H<sub>5</sub>)<sub>5</sub> as a precursor. X-ray diffraction studies determined that the sol-gel films, heat treated at temperatures below 400 {\textdegree}C, were amorphous. Films heat treated at higher temperatures were crystalline Ta<sub>2</sub>O<sub>5</sub>. The solar transmission values (Ts) of tantala films on glass generally range from 0.8-0.9 depending on thickness. The refractive index and the extinction coefficient were evaluated from transmittance characteristics in the UV-VIS-NIR regions. The refractive index values calculated at λ=550 nm increased from n=1.78 to 1.97 with increasing heat treatment from 150 to 450 {\textdegree}C. The films heat treated at different temperatures showed low absorption with extinction coefficients of less than k=1 x 10<sup>-3</sup> in the visible range. Spectrophotometric and impedance spectroscopic investigations performed on Ta<sub>2</sub>O<sub>5</sub> films revealed that these films have protonic conductivity of 3.2 x 10<sup>-6</sup> S/cm. The films are suitable for proton conducting layers in electrochromic (EC) devices.</p>},
	keywords = {electrochromic devices, optical proterties, proton conductor, tantalum oxide},
	author = {Nilg{\"u}n {\"O}zer and Carl M Lampert}
}
