%0 Conference Paper
%A Nilgün Özer
%A Carl M Lampert
%B Window Innovations 95 Conference Proceedings
%C Toronto, Canada
%D 1995
%G eng
%L LBL-38526
%T Sol-Gel Deposited Amorphous Tantalum Oxide and Niobium Oxide Films as Protonic Conductors
%1 <p>Windows and Daylighting Group</p>
%2 LBL-38526
%8 06/1995
%X <p>In this work we report on the preparation of tantalum oxide and niobium oxide films by the sol-gel method for use as proton ion conductors in electrochromic devices. Measurement of the proton conductivity was derived from impedence spectroscopy measurements. The proton conductivity for Ta<sub>2</sub>O<sub>5</sub> and NbO<sub>5</sub> films was 4.6 x 10<sup>-6</sup> Scm<sup>-1</sup> and 3.2 x 10<sup>-7</sup> Scm<sup>-1</sup> respectively. The structural and chemical properties of the films were investigated by X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscopy. These films were found to be amorphous and close to the stoichometry of Ta<sub>2</sub>O<sub>5</sub> and NbO<sub>5</sub> respectively. In order to estimate the compatibility of these sol-gel deposited layers as ion conductors for EC devices, we investigated tantalum oxide and niobium oxide films deposited on sputtered WO<sub>3</sub> films. Charge balance and coloration characteristics were investigated during voltammetric cycling in a pH 2 liquid electrolyte. Spectral transmittance was measured for colored and bleached conditions. The photopic weighted transmittance change and solar weighted transmittance change were T<sub>p</sub>=35.2% - 21.8% and T<sub>s</sub>=75.7% - 14.2% for tantala films on tungsten oxide. For niobia on tungsten oxide the values were T<sub>p</sub>=85.3% - 35.2% and T<sub>s</sub>=75.8% - 28.1%.</p>