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Principles of Electrochromism as Related to Display Applications

  • H. R. Zeller

Abstract

In electrochromic materials an electric current induces a persistent and reversible change in optical properties. The elementary process of coloration consists either in a valency change of one of the constituent ions or in the formation of a color center associated with a lattice defect. Both can be regarded as electrochemical processes and Smakula’s equation directly predicts the electrical charge required to achieve a given contrast. For charge neutrality reasons two species of charge carriers (electrons and ions) are needed to induce coloration. In order to make bulk electrochromism feasible, the material has to be both electronically and ionically conducting. The underlying general physical principles provide clear guidelines in materials research and cell design and will be discussed with emphasis on WO3 and solid state technology.

Keywords

Switching Rate Mixed Conductor Valency Change Electrochromic Material Charge Transfer Absorption Band 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    F. Seitz, Rev. Modern Phys. 26 (1954) 7ADSCrossRefGoogle Scholar
  2. 2.
    I. F. Chang, B. L Gilbert and T. I. Sun (J. Electrochem. Soc. 122 (1975) 955) have coined the work “electrochemichromism” which is more exact than the historical “electrochromism”CrossRefGoogle Scholar
  3. 3.
    S. K. Deb, Phil. Mag. 27 (1973) 801ADSCrossRefGoogle Scholar
  4. 4.
    S. K. Deb and J. A. Chopvorian, J. Appl. Phys. 37 (1966) 4818ADSCrossRefGoogle Scholar
  5. 5.
    S. K. Deb, Appl. Optics Suppl. 3 (1969) 192Google Scholar
  6. 6.
    B. W. Fanghnan, R. S. Crandall and P. M. Heyman, RCA Review 36 (March 1975) 177Google Scholar
  7. 7.
    C. J. Schoot, J. J Ponjee, H. T. van Dam, R. A. van Doom and P. R. Bolwjis, Appl. Phys. Lett. 23 (1973) 64ADSCrossRefGoogle Scholar
  8. 8.
    H. T. van Dam and J. J. Ponjee, J. Electrochem. Soc. 121 (1974) 1555CrossRefGoogle Scholar
  9. 9.
    A. Smakula, Z. Phys. 59 (1930) 603ADSCrossRefGoogle Scholar
  10. 10.
    S. K. Deb and R. F. Shaw, US Patent 3 521 941Google Scholar
  11. 11.
    W. van Gool (ed.), ‘Fast Ion Transport in Solids, Solid State Batteries and Devices’, North Holland, Amsterdam (1973)Google Scholar
  12. 12.
    D. L. Dexter, in F. Seitz and D. Turnbull (eds.), ‘Solid State Physics’ 6 (1958) 353Google Scholar
  13. 13.
    M. B. Robin and P Day, Adv. Inorg. Chem. and Radiochem. 10 (1967) 247CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1976

Authors and Affiliations

  • H. R. Zeller
    • 1
  1. 1.Brown Boveri Research CenterBadenSwitzerland

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