Studies on the Electrochemical Properties of $TiO_{2-x}$ Thin Films

$TiO_{2-x}$ 박막의 전기화학적 성질에 관한 연구

  • Q Won Choi (Department of Chemistry, Seoul National University) ;
  • Chu Hyun Choe (Department of Chemistry, Chonnam National University) ;
  • Ki Hyung Chjo (Department of Chemistry, Chonnam National University) ;
  • Yong Kook Choi (Department of Chemistry, Chonnam National University)
  • 최규원 (서울대학교 자연과학대학 화학과) ;
  • 최주현 (전남대학교 자연과학대학 화학과) ;
  • 조기형 (전남대학교 자연과학대학 화학과) ;
  • 최용국 (전남대학교 자연과학대학 화학과)
  • Published : 1986.02.20

Abstract

A titanium oxide thin films were prepared by air oxidation and vapour oxidation and a $TiO_2$ single crystal was reduced by heating in an argon atmosphere. All the electrode characteristics of the Ti$O_{2-x}$, thin films are not different from those of slightly reduced single crystal rutile. In cyclic voltammogram of oxygen containing electrolyte solution at Ti$O_{2-x}$ electrodes, cathodic peaks were observed at between -0.8V and -1.0V vs. SCE. The cathodic current near 0V vs. SCE in saturated solution with nitrogen was observed to be greater than in saturated solution with air. The chronoamperogram was represented by the equation of i = $i_0e^{-kt}$, when the rate constant k was represented by the equation of k =$k_0{[H^+]}^nexp(A{\eta}+E_a/RT)$ The values of activation energy $E_a $were found to be 4.6~4.8kcal/mole in overpotential range of 0.035∼0.145 V and 1.6kcal/mole in overpotential range of 0.2∼0.5V. The values of n and A were found to be 0. 1 and 5.4~5.6/V in range of 0.035~0.145V, and in range of 0.2~0.5V, to be 0.04 and 1.3/V, respectively. This can be interpreted as an totally irreversible reduction of oxygen.

Keywords

References

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