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Enhanced electrochromic properties of heat treated nanostructured tungsten trioxide thin films

Published online by Cambridge University Press:  31 January 2011

Gisia Beydaghyan ,
Jean-Luc M. Renaud ,
Georges Bader  and
P.V. Ashrit
Gisia Beydaghyan*
Affiliation:
Thin Films and Photonics Research Group (GCMP), Department of Physics and Astronomy, Université de Moncton, Moncton, N.B., Canada E1A 3E9
Jean-Luc M. Renaud
Affiliation:
Thin Films and Photonics Research Group (GCMP), Department of Physics and Astronomy, Université de Moncton, Moncton, N.B., Canada E1A 3E9
Georges Bader
Affiliation:
Thin Films and Photonics Research Group (GCMP), Department of Physics and Astronomy, Université de Moncton, Moncton, N.B., Canada E1A 3E9
P.V. Ashrit
Affiliation:
Thin Films and Photonics Research Group (GCMP), Department of Physics and Astronomy, Université de Moncton, Moncton, N.B., Canada E1A 3E9
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Nanostructured tungsten trioxide films were fabricated with the technique of glancing angle deposition (GLAD) in a thermal evaporation chamber with a base pressure of 1.3 × 10−4 Pa. Films were deposited at vapor incidence angles of 0°, 20°, 40°, and 50° with film thickness varying between 160 and 200 nm, as determined by spectroscopic ellipsometry. After deposition, samples were heated for 1 h in air at 400 °C and were subsequently intercalated with small amounts (5 to 15 nm) of lithium by dry lithiation, a technique developed in our laboratory. Compared with our previous work on as-deposited nanostructured films, these samples showed significantly enhanced coloration in the infrared region. It was found that the films exhibited an absorption- based coloration in the lower wavelengths as well as an increased reflection in the infrared region. Morphological investigation by atomic force microscopy (AFM) showed grain agglomeration and increased surface roughness upon heating. Our studies further indicate that grain agglomeration significantly contributes to the superior coloration properties of the films.

Keywords

Thin filmOptical propertiesNanostructure
Type
Articles
Information
Journal of Materials Research , Volume 23 , Issue 1 , January 2008 , pp. 274 - 280
Copyright
Copyright © Materials Research Society 2008

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References

REFERENCES

1Granqvist, C.G.: Handbook of Inorganic Electrochromic Materials Elsevier Amsterdam 1995Google Scholar
2Granqvist, C.G.: Progress in electrochromics: Tungsten oxide revisited. Electrochim. Acta 44, 3005 1999CrossRefGoogle Scholar
3Ashrit, P.V., Bader, G.Truong, V.: Electrochromic properties of nanocrystalline tungsten oxide thin films. Thin Solid Films 320, 324 1998CrossRefGoogle Scholar
4Ashrit, P.V.: Dry lithiation study of nanocrystalline, polycrystalline and amorphous tungsten trioxide thin-films. Thin Solid Films 385, 81 2001CrossRefGoogle Scholar
5Bonhôte, P., Gogniat, E., Grätzel, M.Ashrit, P.V.: Novel electrochromic devices based on complementary nanocrystalline TiO2 and WO3 films. Thin Solid Films 350, 269 1999CrossRefGoogle Scholar
6Beydaghyan, G., Bader, G.Ashrit, P.V.: Electrochromic and morphological investigation of dry-lithiated nanostructured tungsten trioxide thin films. Thin Solid Films doi: 10.1016/j.tsf.2007.05.006 (in press)Google Scholar
7Bader, G., Ashrit, P.V.Truong, V.: Transmission and reflection ellipsometry of thin films and multilayer systems. Appl. Opt. 37, 1146 1998CrossRefGoogle ScholarPubMed
8Ashrit, P.V., Bader, G., Girouard, F.E.Truong, V.: Electrochromic materials for “smart” window applications. Proc. SPIE 1401, 119 1991CrossRefGoogle Scholar
9Buzea, C., Beydaghyan, G., Elliot, C.Robbie, K.: Control of power law scaling in the growth of silicon nanocolumn pseudo-regular arrays deposited by glancing angle deposition. Nanotechnology 16, 1986 2005CrossRefGoogle ScholarPubMed
10Yoldas, B.E.Partlow, D.P.: Investigation of porous oxides as an antireflection coating for glass surfaces. Appl. Opt. 23, 1418 1984CrossRefGoogle Scholar
11Granqvist, C.G.: Handbook of Inorganic Electrochromic Materials Elsevier Amsterdam 1995 31–33Google Scholar
12Granqvist, C.G.: Handbook of Inorganic Electrochromic Materials Elsevier Amsterdam 1995 50–5161–63Google Scholar
13Granqvist, C.G.: Handbook of Inorganic Electrochromic Materials Elsevier Amsterdam 1995 81–87Google Scholar
14Galyamov, B.Sh.Roginskaya, Yu.E.: Percolation transitions in WO3 electrochromium films. Zh. Tekn. Fiz. 14, 280 1988Google Scholar
15Vértes, A.Schiller, R.: Concentration-dependent diffusivity: Hydrogen percolation in WO3. J. Appl. Phys. 54, 199 1983CrossRefGoogle Scholar
16Bellac, D. Le, Azens, A.Granqvist, C.G.: Angular selective transmittance through electrochromic tungsten oxide films made by oblique angle sputtering. Appl. Phys. Lett. 66, 1715 1995CrossRefGoogle Scholar