Abstract

MILARE, E.; IONASHIRO, E. Y.; BENEDETTI, A. V.  and  FERTONANI, F. L.. Contribution to the Study of Ir Electrodes in Aqueous Solution of KNO₃/HNO₃ and KNO₃/HNO₃/Hg₂(NO₃)₂. Port. Electrochim. Acta [online]. 2003, vol.21, n.2, pp.155-169. ISSN 0872-1904.

Cyclic voltammetry and surface analysis techniques (EDX microanalysis, mapping of elements and SEM images) have been used to study the solid state reactions of Ir in blank solution or Hg(I)-containing solution. The studies in KNO₃/HNO₃ solution permit to suggest the formation of a thin oxide layer film deposited in the substrate. The RCV process exhibits the decrease of capacitive current associated to the substrate surface restructuring. The electro deposition of Hg occurs initially in UPD condition from Hg(I)-containing solution, C_Hg(I) = 3.51x10^-7 mol L^-1. The electro deposition of bulk mercury occurs from Hg(I)-containing solution, C_Hg(I) = 3.51x10^-5 mol L^-1. It was observed the deposition of Hg in the substrate in open circuit for all employed conditions.

Keywords : iridium; mercury; cyclic voltammetry; UPD.

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