Preparation of a platinum layer-modified aluminum electrode by electrochemical and electroless cementations and its use for the electrooxidation of methanol

The deposition of platinum on the aluminum electrode by two methods involving electroplating by single step potential from an aqueous buffered H2PtCl6 solution (pH 7) and electroless cementation from an aqueous solution of H2PtCl6 saturated with NaF is described. The electrochemical characteristic of the platinum layer-modified aluminum electrode (Pt/Al) in aqueous solution with various pHs was investigated. The Pt/Al layers were characterized by imaging with scanning electron microscopy and optimum conditions for the preparation of the Pt/Al modified electrode was chosen. The modified electrode was used as electrocatalyst for the electrooxidation of methanol in 0.1 M H2SO4 solution. After characterization of some features of the electrochemical system on the stationary and rotating electrode, an oxidation pathway is suggested. The current density of the methanol oxidation at Pt/Al electrode measured in optimized conditions and compared with that obtained on the smooth Pt, Pt/Pt, and Pt/PoPD/Pt electrocatalysts. The stability of the electrode was followed over the course of the time and its stability and reproducibility was confirmed.