In recent decades, due to high-energy demands, fossil fuel depletions, and environmental pollution throughout the world [1], there has been an increasing interest in the development of fuel cells, because they can directly convert chemical energy to electrical energy with higher efficiency than other sources of 103 electrical power [2]. Among fuel cells, the direct methanol fuel cell (DMFC) is one of the most attractive ones because of high energy conversion efficiency and very low environmental intrusion and without reformer [3]. In this paper, SiO2@Cu2O @Au core/shell/shell nanoparticles were synthesized by reducing Cu2O on APTES (3-aminopropyltriethoxysilane) molecules attached silica nanoparticle cores for several stages. Cu2O nanoparticles where synthesized readily with size of 4-5nm using a simple route of sol-gel method. The thickness of Au shell altered with repeating the stage of reducing HAuCl4 on SiO2@Cu2O. The presence of gold and Cu2O coating was confirmed by XRD, TEM and FTIR. The TEM images indicated that the silica nanoparticles were spherical in shape with 100 nm diameters and functionalizing silica nanoparticles with a layer of bifunctional APTES (3-aminopropyltriethoxysilane) molecules, and THPC (Tetrakis hydroxyl methyl phosphonium chloride) gold nanoparticles in narrow size of < 5nm. In order to construct the electrode, a solution of Chitosan (0.50%) was prepared by dissolving CH in acetate buffer. Then the SiO2@Cu2O@Au core/shell/shell nanoparticles was dispersed in the CH solution by sonicating at room temperature. The SiO2@Cu2O@Au core/shell/shell–chitosan was casted on the surface of glassy carbon electrode and allowing it to dry at room temperature for about 12 h. Then its surface was potentiostatically coated with platinum nanoparticles at constant potential of –0.2 V (vs. SCE). The electrocatalytic oxidation of methanol at the SiO2@Cu2O@Au core/shell/shell–chitosan–platinum nanocomposite has been investigated using cyclic voltammetric and chronoamperometric methods. The results show that the presence of SiO2@Cu2O@Au core/shell/shell–chitosan nanocomposite improves considerably the efficiency of deposited Pt nanoparticles toward the oxidation of methanol. The effects of various parameters on electrocatalytic oxidation of the methanol were investigated.

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