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The influence of microstructure on the electrochromic properties of LixWO3 thin films: Part I. Ion diffusion and electrochromic properties

Published online by Cambridge University Press:  03 March 2011

Ji-Guang Zhang
Affiliation:
National Renewable Energy Laboratory, Golden, Colorado 80401-3393
Edwin C. Tracy
Affiliation:
National Renewable Energy Laboratory, Golden, Colorado 80401-3393
David K. Benson
Affiliation:
National Renewable Energy Laboratory, Golden, Colorado 80401-3393
Satyen K. Deb
Affiliation:
National Renewable Energy Laboratory, Golden, Colorado 80401-3393
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Abstract

The chemical diffusion coefficients of lithium ions in LixWO3 films were investigated as a function of lithium concentration and film porosity. Thin films were deposited with different porosities by thermal evaporation of WO3 powder in various partial water pressures. Our results indicate that diffusion coefficients increase with film porosity and decrease with increasing lithium concentration. Large diffusion coefficients that were found for small lithium concentrations appear to be due to the contribution of protons generated from ion exchange reactions between lithium and water incorporated in the film. Simultaneous electrical and in situ optical measurements were carried out to study the effect of porosity on the electrochromic properties of LixWO3. The coloring efficiency of porous WO3 films increases by approximately 70% when deposited in partial water pressure of 10−4 Torr, but decreases with further increments in water pressure.

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Articles
Copyright
Copyright © Materials Research Society 1993

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References

REFERENCES

1Deb, S. K., Philos. Mag. 27, 801 (1973).CrossRefGoogle Scholar
2Lampert, C. M. and Granqvist, C. G., in Large Area Chromogenics: Materials and Devices for Transmittance Control, SPIE IS 4, 2 (1990).Google Scholar
3Deb, S. K., Sol. Energy Mater. 25, 327 (1992).CrossRefGoogle Scholar
4Rauh, R. D. and Cogan, S. F., Proc. 25th IECEC 4, 26 (1990).Google Scholar
5Goldner, R. B., Amtz, F. O., Berera, G., Haas, T. E., Wei, G., Wong, K. K., and Yu, P. C., Solid State Ionics, October (1991).Google Scholar
6Bange, K. and Gambke, T., Adv. Mater. 2, 10 (1990).CrossRefGoogle Scholar
7Benson, D. K. and Tracy, C. E., Chemtech, November, 677 (1991).Google Scholar
8Green, M. and Weiner, J. A., Thin Solid Films 38, 89 (1976).CrossRefGoogle Scholar
9Mohapatra, S. K., J. Electrochem. Soc. 125, 284 (1978).CrossRefGoogle Scholar
10Nagai, J. and Kamimori, T., Jpn. J. Appl. Phys. 22, 681 (1983).CrossRefGoogle Scholar
11Bohnke, O., Bohnke, C., and Robert, G., Solid State Ionics 6, 121 (1982).CrossRefGoogle Scholar
12Zhang, J-G., Benson, D. K., Tracy, C. E., and Deb, S. K., J. Mater. Res. 8, 2657 (1993).CrossRefGoogle Scholar
13Weppner, W. and Huggins, R. A., J. Electrochem. Soc. 124, 1569 (1977).CrossRefGoogle Scholar
14Bohnke, C. and Bohnke, O., Solid State Ionics 39, 195 (1990).CrossRefGoogle Scholar
15Schlotter, P. and Pickelmann, L., J. Electron. Mat. 4, 207 (1982).CrossRefGoogle Scholar
16Zeller, H. R. and Beyeler, H. U., Appl. Phys. 13, 231 (1977).CrossRefGoogle Scholar
17Benson, D. K., Tracy, C. E., Svensson, J. S. E. M., and Liebert, B. E., in Optical Materials Technology for Energy Efficiency and Solar Energy Conversion VI, SPIE 823, 72 (1987).CrossRefGoogle Scholar
18Ho, C., Raistrick, I. D., and Huggins, R. A., J. Electrochem. Soc. 127, 343 (1980).CrossRefGoogle Scholar
19Nagai, J., Kamimori, T., and Mizuhashi, M., Reports Res. Lab. Asahi Glass Co., Ltd., 36, 135 (1986).Google Scholar
20Faughnan, B. W., Crandall, R. S., and Heyman, P. M., RCA Rev. 36, 177 (1975).Google Scholar
21Nagao, M., J. Phys. Chem. 75, 3822 (1971).CrossRefGoogle Scholar
22Primet, M., Pichat, P., and Mathieu, M. V., J. Phys. Chem. 75, 1216 (1971).CrossRefGoogle Scholar