Preparation of Multilayer Films Containing Pt Nanoparticles on a Glassy Carbon Electrode and Application as an Electrocatalyst for Dioxygen Reduction

In this paper, a simple route for the preparation of Pt nanoparticles is described. PtCl 6 2 - and [tetrakis( N -methylpyridyl)porphyrinato]cobalt (CoTMPyP) were assembled on a 4-aminobenzoic acid modified glassy carbon electrode through the layer-by-layer method. The three-dimensional Pt nanoparticle films are directly formed on an electrode surface by electrochemical reduction of PtCl 6 2 - sandwiched between CoTMPyP layers. Regular growth of the multilayer films is monitored by UV−vis spectroscopy. X-ray photoelectron spectroscopy verifies the constant composition of the multilayer films containing Pt nanoparticles. Atomic force microscopy proves that the as-prepared Pt nanoparticles are uniformily distributed with average particle diameters of 6−10 nm. The resulting multilayer films containing Pt nanoparticles on the modified electrode possess catalytic activity for the reduction of dissolved oxygen. Rotating disk electrode voltammetry and rotating ring-disk electrode voltammetry confirm that Pt nanoparticle containing films can catalyze an almost four-electron reduction of O 2 to water in 0.5 M H 2 SO 4 solution.