Russian Journal of Electrochemistry

, Volume 37, Issue 10, pp 1065–1071 | Cite as

Charge Accumulation in Nanoheterogeneous Iridium Oxide Films

  • Yu. E. Roginskaya
  • M. D. Gol'dshtein
  • O. V. Morozova
  • L. D. Glazunova
Article

Abstract

Iridium oxide films with different values of crystallinity degree K are synthesized. Properties of the films and their morphological features are examined. The charging of the films in a 1 M H2SO4solution is studied voltammetrically. The most amorphous films (K = 0.08–0.26) acquire the largest overall charge q(in a fixed potential range) relative to films with higher crystallinity degrees; however, the qvs. K dependence is not additive, and the charge remains virtually invariant beginning with K ≥ 0.26. The contribution of slow charging processes, which is quite perceptible in the amorphous films, is absent in samples with higher crystallinity degrees, which have faster charge kinetics. The fast charging processes, which are not limited by diffusion, occur in boundary regions of IrO2crystallites (and/or the “oxide” part of a crystalline hydrated iridium oxide) and the amorphous phase. The transport of charge-compensating ions in the boundary regions occurs without considerable complications, as in the loose network of amorphous phase IrO2· xH2O. The assumption about the formation of a “metallic” highly-conducting IrO2cluster at K ≥ 0.26 is substantiated. The cluster rules out large resistances in the course of charge transport, which is a possible reason for the slow charging of amorphous films with K < 0.26.

Keywords

Amorphous Phase Iridium Boundary Region IrO2 Charge Process 
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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Copyright information

© MAIK “Nauka/Interperiodica” 2001

Authors and Affiliations

  • Yu. E. Roginskaya
    • 1
  • M. D. Gol'dshtein
    • 1
  • O. V. Morozova
    • 1
  • L. D. Glazunova
    • 1
  1. 1.Russian Federation Scientific Center“Karpov Research Institute of Physical Chemistry,”MoscowRussia

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