Novel electrode materials based on ion beam induced deposition of platinum carbon composites

Untreated and thermally annealed platinum carbon (PtC) composites obtained by ion beam induced deposition (IBID) are physically and electrochemically characterized as novel patternable electrode materials. Energy dispersive X-ray spectroscopy (EDX) and Raman spectroscopy reveal that annealing in ambient atmosphere and at temperatures above 400 °C substantially reduces the amount of carbon within the deposited material. Raman spectra also show that at elevated temperatures carbon rearranges into a more structured graphitic-like phase. Atomic force microscopy (AFM) reveals that after the annealing procedure the surface structure appears more corrugated, while the dimensions of granular surface features decreases. Furthermore, it is shown that electrodes based on annealed PtC material show an improved heterogeneous electron transfer rate for the oxidation of potassium hexacyanoferrate(II) trihydrate by almost three orders of magnitude, whereas the reduction of hexaammineruthenium(III) trichloride proceeds at similar rates for both treated and untreated electrodes. The rate of electrochemical oxidation of H2O2, which is influenced by the composition of the electrode surface, is also improved at thermally annealed electrodes. Finally, cyclic voltammetry in sulfuric acid shows an increase in surficial platinum concentration after annealing of the material.