Physicochemical properties of thermally prepared Ti-supported IrO2+ ZrO2 electrocatalysts

doi:10.1016/0022-0728(94)03614-4

Journal of Electroanalytical Chemistry

Volume 376, Issues 1–2, 10 October 1994, Pages 195-202

https://doi.org/10.1016/0022-0728(94)03614-4 Get rights and content

Abstract

Thermally prepared mixed-oxide IrO₂ + ZrO₂ films have been studied by Rutherford backscattering spectrometry (RBS), wide-angle X-ray scattering (WAXS) and cyclic voltammetry. Concentration depth profiling by RBS has shown that electrode films containing less than 50 mol.% of iridium dioxide have layered structures where noble metal oxide and zirconium oxide enrichments alternate. The outermost layer is enriched with iridium oxide. By WAXS analysis it was possible to prove the existence of an IrO₂ and a ZrO₂ phase. From cell parameters, very limited solubility could be ascertained, restricted at the two limits of the composition coordinate. In the range 0–20 mol.% of iridium dioxide, a tetragonal ZrO₂ phase is formed. For samples richer in IrO₂, the ZrO₂ phase becomes amorphous. The microstructural features of the tetragonal IrO₂-rich phase do not change significantly with the film composition. The effective surface area of the samples, as determined by cyclic voltammetry, exhibits a maximum in the composition range 50–80 mol.% IrO₂. This result has been interpreted on the basis of WAXS and RBS data.

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^☆: In honour of Antoinette Hamelin on the occasion of her birthday.

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Physicochemical properties of thermally prepared Ti-supported IrO2+ ZrO2 electrocatalysts☆

Abstract

Electrochim. Acta

Electrochim. Acta

Thermochim. Acta

J. Electroanal. Chem.

Electrochim. Acta

J. Electroanal. Chem.

Surf. Sci.

J. Electroanal. Chem.

J. Electroanal. Chem.

Mater. Chem. Phys.

J. Electroanal. Chem.

Chimia

J. Appl. Electrochem.

J. Appl. Electrochem.

J. Chem. Soc. Faraday Trans.

J. Phys. Chem.

J. Phys. Chem.

J. Mater. Res.

J. Mater. Res.

Physicochemical properties of thermally prepared Ti-supported IrO₂+ ZrO₂ electrocatalysts☆