Thermal preparation of thin platinum coatings and their electrochemical and atomic force microscopic characterization

Platinum coatings were thermally prepared on glass substrates. Hexachloroplatinic acid was used as a starting material for platinum. The thermal behaviour of H2PtCl6 in the absence and presence of organic additives was investigated by thermogravimetry. X-ray diffractograms indicated the presence of crystalline Pt deposits. The examination of the surface morphology of the Pt coating by atomic force microscopy revealed that the surface roughness of coatings increased with increasing number of coating cycles. The sheet resistance of Pt coatings decreased with an increase in the number of coating cycles. The twice-coated electrode showed a typical cyclic–voltammetric response of platinum in 0.5 M H2SO4. The Fe CN.63yr4y couple was used as a suitable test system for the Pt-coating electrodes. On the basis of the results obtained, it can be concluded that at least three coating cycles are required to be applied in order to obtain an electrode of good electrochemical performance. q2000 Elsevier Science B.V. All rights reserved.