Mansoura University, Egypt
Title: Comparison between Sn modified single crystal and preferentially Pt electrodes towards ethanol oxidation in acidic medium
Biography: A A El-Shafei
Polycrystalline, preferentially oriented and low-index plane Pt single crystal electrodes modified by submonolayer deposition of Sn have been tested for ethanol oxidation in acidic media using cyclic voltammetry and chronoamperometry. In contrast to spontaneous deposition, forced deposition facilitates the irreversible adsorption of Sn particularly on Pt (110), and allows the study of electrochemical activity of Sn modified Pt with all electrodes understudy. For all substrate planes, Sn adlayer enhance the current greatly by the ethanol oxidation process. The enhancement factor for ethanol oxidation depends on both substrate crystallography and Sn coverage. The optimum coverage was found to vary from 0.2 for Pt (100) to around 0.6 for preferentially oriented t“(100)". Preferentially oriented Sn/Pt"(110)" exhibited the highest enhancement factor towards ethanol oxidation. On the other hand, the lowest tolerance ability was found to be Sn modified Pt (111). This was attributed to the accumulation of acetate species at the electrode surface.