Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-26T21:10:11.342Z Has data issue: false hasContentIssue false

Structure–property correlation of nanostructured WO3 thin films produced by electrodeposition

Published online by Cambridge University Press:  03 March 2011

M. Deepa
Affiliation:
National Physical Laboratory, New Delhi 110012, India
A.K. Srivastava
Affiliation:
National Physical Laboratory, New Delhi 110012, India
S. Singh
Affiliation:
National Physical Laboratory, New Delhi 110012, India
S.A. Agnihotry
Affiliation:
National Physical Laboratory, New Delhi 110012, India
Get access

Abstract

Nanocrystalline tungsten oxide (WO3) films were electrodeposited potentiostatically at room temperature on transparent conducting substrates from an ethanolic solution of acetylated peroxotungstic acid prepared from a wet chemistry process. The changes that occur in the microstructure and the grain size of the as-deposited WO3 films as a function of annealing temperature are simultaneously accompanied by a continually varying electrochromic performance. X-ray diffraction studies revealed the transformation of a nanocrystalline as-deposited WO3 film into a highly crystalline triclinic WO3 as the annealing temperature was raised from room temperature to 500 °C. The microstructural evolution with the increasing annealing temperature of the as-deposited film was further exemplified by transmission electron microscopy (TEM) studies. While the as-deposited film was composed of uniformly distributed ultra fine nanograins, the most noticeable feature seen in these films annealed at 250 °C was the presence of open channels which are believed to promote lithium ion motion. Films annealed at 400 °C exhibited coarse grains with prominent grain boundaries that hinder lithium ion movement, which in turn reduces the film’s ion insertion capacity. In concordance with the TEM results, the 250 °C film had the highest ion storage capacity as it exhibited a charge density of 67.4 mC cm−2 μm−1. The effect of microstructure was also reflected in the high transmission modulation (64%) and coloration efficiency (118 cm2 C−1) of the 250 °C film at 632.8 nm. Contrary to the superior electrochromic performance of the 250 °C film, the optical switching speeds between the colored and bleached states of the as-deposited WO3 film declined considerably as a function of annealing temperature. Also, the diffusion coefficient for lithium ions was greater by at least an order of magnitude for the as-deposited film as compared to the 250 and 500 °C films. In this report, the influence of microstructural changes that are brought about by the annealing of the as-deposited WO3 films on their coloration-bleaching dynamics is evaluated in terms of their structural, electrochromic, and electrochemical properties.

Type
Articles
Copyright
Copyright © Materials Research Society 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Granqvist, C.G. In Handbook of Inorganic Electrochromic Materials (Elsevier Science B.V., Amsterdam, The Netherlands, 1995), Introduction, p. 1.Google Scholar
2.Biswas, P.K., Pramnik, N.C., Mahapatra, M.K., Ganguli, D. andLivage, J.: Optical and electrochromic properties of sol-gel WO3 films on conducting glass. Mater. Lett. 57, 4429 (2003).CrossRefGoogle Scholar
3.Aliev, A.E. andShin, H.W.: Nanostructured materials for electrochromic devices. Solid State Ionics 154-155, 425 (2002).CrossRefGoogle Scholar
4.Heckner, K.H. andKraft, A.: Similarities between electrochromic windows and thin film batteries. Solid State Ionics 152-153, 899 (2002).CrossRefGoogle Scholar
5.Bange, K.: Coloration of tungsten oxide films: A model for optically active coatings. Sol. Energy Mater. Sol. Cells 58, 1 (1999).CrossRefGoogle Scholar
6.Granqvist, C.G.: Electrochromic tungsten oxide films: Review of progress 1993-1998. Sol. Energy Mater. Sol. Cells 60, 201 (2000).CrossRefGoogle Scholar
7.Santato, C., Odziemkopwski, M., Ulmann, M. andAugustynski, J.: Crystallographically oriented mesoporous WO3 films: Synthesis, characterization and applications. J. Am. Chem. Soc. 123, 10639 (2001).CrossRefGoogle ScholarPubMed
8.Mohammad, A.A. andGillet, M.: Phase transformations in WO3 thin films during annealing. Thin Solid Films 408, 302 (2002).CrossRefGoogle Scholar
9.Wang, H., Xu, P. andWang, T.: The preparation and properties study of photocatalytic nanocrystalline / nanoporous WO3 thin films. Mater. Des. 23, 331 (2002).CrossRefGoogle Scholar
10.Regragui, M., Addou, M., Outzourhit, A., Idirissi, E.E., Kachnouane, A. andBougrine, A.: Electrochromic effect in WO3 thin films prepared by spray pyrolysis. Sol. Energy Mater. Sol. Cells 77, 341 (2003).CrossRefGoogle Scholar
11.Pyper, O., Schollhorn, R., Donkers, J.J.T.M. andKrings, L.H.M.: Nanocrystalline structure of WO3 thin films prepared by the sol-gel technique. Mater. Res. Bull. 33, 1095 (1998).CrossRefGoogle Scholar
12.Shen, P.K., Huang, H.T. andTseung, A.C.C.: A study of tungsten oxide and polyaniline composite films, I. Electrochemical and electrochromic behavior. J. Electrochem. Soc. 139, 1840 (1992).CrossRefGoogle Scholar
13.Taylor, D.J., Cronin, J.P., Allard, L.F. andBirnie, D.P.: Microstructure of laser-fired, sol-gel derived tungsten oxide films. Chem. Mater. 8, 1396 (1996).CrossRefGoogle Scholar
14.Cronin, J.P., Kennedy, S.R., Agrawal, A., Gudgel, T.J., Yao, Y.J., Tonazzi, J.C.L. andUhlmann, D.R.: Properties of WO3 coatings for large area electrochromic devices. Electrochemistry of glasses and ceramics. Ceram. Trans. 92, 175 (1999).Google Scholar
15.Sharma, N., Deepa, M., Varshney, P. andAgnihotry, S.A.: Influence of organic additive on the morphological, electrical and electrochromic properties of sol-gel derived WO3 coatings. J. Sol-Gel Sci. Technol. 18, 167 (2000).CrossRefGoogle Scholar
16.Vijaylakshmi, R., Jayachandran, M. andSanjeeviraja, S.: Structural, electrochromic and FTIR studies on electrodeposited tungsten trioxide films. Curr. Appl. Phys. 3, 171 (2003).CrossRefGoogle Scholar
17.Habazaki, H., Hayashi, Y. andKonno, H.: Characterization of electrodeposited WO3 films and its application to electrochemical wastewater treatment. Electrochim. Acta 47, 4181 (2002).CrossRefGoogle Scholar
18.Shiyanovskaya, I., Hepel, M. andTewksburry, E.: Electrochromism in electrodeposited nanocrystalline WO3 films, I. Electrochemical and optical properties. J. New Mater. Electrochem. Syst. 3, 241 (2000).Google Scholar
19.Yamanaka, K.: Electrodeposited films from aqueous tungstic acid - hydrogen peroxide solutions for electrochromic display devices. Jpn. J. Appl. Phys. 26, 1884 (1987).CrossRefGoogle Scholar
20.Su, L., Zhang, L., Fang, J., Xu, M. andLu, Z.: Electrochromic and photoelectrochemical behavior of electrodeposited tungsten trioxide films. Sol. Energy Mater. Sol. Cells 58, 133 (1999).CrossRefGoogle Scholar
21.Yu, Z., Jia, X., Du, J. andZhang, J.: Electrochromic WO3 films prepared by a new electrodeposition method. Sol. Energy Mater. Sol. Cells 64, 55 (2000).CrossRefGoogle Scholar
22.Kudo, T.: A new heteropolyacid with carbon as a hetero atom in a Keggin like structure. Nature 312, 537 (1984).CrossRefGoogle Scholar
23.Pennisi, A., Simone, F. andLampert, C.M.: Electrochromic properties of tungsten- molybdenum oxide electrodes. Sol. Energy Mater. Sol. Cells 28, 233 (1992).CrossRefGoogle Scholar
24.Agnihotry, S.A., Ramachandran, R., Varshney, P., Sharma, N. andDeepa, M.A process for the preparation of highly stable solid precursor material useful for tungsten oxide based electrochromic coatings. Patent Appl. No. 131/DEL/2000 (U.K., India, 2000).Google Scholar
25.Cullity, B.D. In Elements of X-ray Diffraction (Addison-Wesley, Reading, MA, 1978). Diffraction IGoogle Scholar
26.Agnihotry, S.A., Sharma, N. andDeepa, M.: Ion-exchange derived precursor materials for deposition of WO3 electrochromic films: Spectroscopic investigations. J. Sol-Gel Sci. Technol. 24, 265 (2002).CrossRefGoogle Scholar
27.Sharma, N., Deepa, M., Varshney, P. andAgnihotry, S.A.: FTIR investigations of tungsten oxide electrochromic films derived from organically modified peroxotungstic acid precursors. Thin Solid Films 401, 45 (2001).CrossRefGoogle Scholar
28.Porqueras, I., Viera, G., Marti, J. andBertran, E.: Deep profiles of lithium in electrolytic structures of ITO/WO3 for electrochromic applications. Thin Solid Films 343-344, 179 (1999).CrossRefGoogle Scholar
29.Lindstrom, T., Kullman, L., Ronnow, D., Ribbing, C.G. andGranqvist, C.G.: Electrochromic control of thin film light scattering. J. Appl. Phys. 81, 1464 (1997).CrossRefGoogle Scholar
30.Faughnan, B.W. andCrandall, R.S. In Topics in Applied Physics, Display Devices, edited by Pankove, J.I. (Springer-Verlag, New York, 1980), p. 181.CrossRefGoogle Scholar
31.Habib, A.M. andGlueck, D.: The electrochromic properties of chemically deposited tungsten oxide films. Sol. Energy Mater. 18, 127 (1989).CrossRefGoogle Scholar
32.Ho, C., Raistrick, I.D. andHuggins, R.A.: Application of A-C techniques to the study of lithium diffusion in tungsten trioxide thin films. J. Electrochem. Soc. 127, 343 (1980).CrossRefGoogle Scholar
33.Pyun, S.I. andBae, J.S.: Lithium ion transport in r.f. magnetron sputtered WO3 film as a function of lithium content. J. Alloys Compd. 245 L1 (1996).CrossRefGoogle Scholar
34.Shen, P.K., Chen, K.Y. andTseung, A.C.C.: Electrochromism of electrodeposited tungsten trioxide films: Electrochemical characterization. J. Electrochem. Soc. 141, 1758 (1994).CrossRefGoogle Scholar
35.Avellaneda, C.O., Bueno, P.R. andBulhoes, L.O.S.: Synthesis and electrochromic behavior of lithium doped electrochromic films. J. Non-Cryst. Solids 290, 115 (2001).CrossRefGoogle Scholar
36.Antonaia, A., Polichetti, T., Addonizio, M.L., Aprea, S., Minarini, C. andRubino, A.: Structural and optical characterization pf amorphous and crystalline evaporated WO3 layers. Thin Solid Films 354, 73 (1999).CrossRefGoogle Scholar