COMPOSITION AND PROPERTIES OF SURFACE LAYERS PREPARED BY ION BEAM-ASSISTED DEPOSITION OF CATALYTIC METALS FROM VACUUM ARC-DISCHARGE PLASMA ON CARBON SUBSTRATES

Surface layers were prepared by ion beam-assisted deposition (IBAD) of platinum and rare earth metals (Ce, Yb) on the carbon-based Toray Carbon Fiber Paper TGP-H-060 T catalyst support in effort to produce electrocatalysts for direct methanol and ethanol oxidation fuel cells (DMFC, DEFC) with polymer electrolyte membrane. The layer formation in the IBAD mode, by means of the metal deposition and the mixing of a precipitating layer with the substrate by accelerated (U = 10 kV) ions of the same metal, was carried out. In this process, a neutral fraction of metal vapor and ionized plasma of vacuum pulsed electric arc was used. The study of morphology and composition of the layers was performed by scanning electron microscopy and electron probe microanalysis, X-ray fluorescence analysis and Rutherford backscattering spectrometry. Properties of the prepared electrocatalysts were investigated by cyclic voltammetry. It was established that the prepared electrocatalysts show their activity in the processes of electrochemical methanol and ethanol oxidation.

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