Advertisement

Journal of Applied Electrochemistry

, Volume 22, Issue 2, pp 156–160 | Cite as

Analysis of nonlinear Mott-Schottky plots obtained from anodically passivating amorphous and polycrystalline TiO2 films

  • Eung-Jo Lee
  • Su-Il Pyun
Papers

Abstract

The present work is concerned with analysis of the nonlinear Mott-Schottky plots obtained from the measured impedances of anodically passivating amorphous and polycrystalline TiO2 films including multiple donor levels. The passivating amorphous TiO2 films were prepared on titanium in 0.5 M H2SO4 solution galvanostatically at 2 mA cm−2 at formation potentials of 2, 3 and 5 V/SCE, and the polycrystalline films at 5 mA cm−2 at potentials of 20 and 30 V/SCE. The analysis was made by obtaining a numerical solution to a modified Mott-Schottky equation by using the Euler method. Based upon the analysis, the applied potential dependence of the donor distribution across the amorphous and polycrystalline TiO2 films was determined for various film thicknesses and measuring frequencies. Ionized donor concentration increases with increasing applied potential, regardless of film thickness and measuring frequency. The thinner film and the lower measuring frequency enhance the donor concentration. It is suggested from the analysis of the nonlinear Mott-Schottky plots that the applied potential dependence of the donor distribution is attributable to the presence of multiple donor levels and that the donor concentration as a function of applied potential is definitely determined by the film thickness and measuring frequency.

Keywords

TiO2 Titanium H2SO4 Film Thickness Measured Impedance 
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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1]
    K. Leitner, J. W. Schultze and U. Stimming,J. Electrochem. Soc. 33 (1986) 1561.Google Scholar
  2. [2]
    M. Nakao, R. Schumacher and R. N. Schindler,ibid.133 (1986) 2308.Google Scholar
  3. [3]
    J. Schoonman, K. Vos and G. Blasse,ibid.128 (1981) 1154.Google Scholar
  4. [4]
    R. M. Torresi, O. R. Camara and C. P. De Pauli,Electrochim. Acta 32 (1987) 1291.Google Scholar
  5. [5]
    M. H. Dean and U. Stimming,Corrosion Science 29 (1989) 199.Google Scholar
  6. [6]
    R. W. Daniels, ‘An Introduction to Numerical Methods and Optimization Techniques’, North Holland, New York (1978) pp. 144–151.Google Scholar
  7. [7]
    W. C. Johnson and P. T. Panousis,IEEE Trans. Electron Devices ED-18 (1971) 965.Google Scholar

Copyright information

© Chapman & Hall 1992

Authors and Affiliations

  • Eung-Jo Lee
    • 1
  • Su-Il Pyun
    • 1
  1. 1.Department of Materials Science and EngineeringKorea Advanced Institute of Science and TechnologySeoulKorea

Personalised recommendations