Electrochemical deposition of platinum nanoparticles in multiwalled carbon nanotube-Nafion composite for methanol electrooxidation

Platinum nanoparticles were successfully deposited within a multiwalled carbon nanotube (MWCNT)-Nafion matrix by a cyclic voltammetry method. A Pt(IV) complex was reduced to platinum nanoparticles on the surface of MWCNTs. The resulting Pt nanoparticles were characterized by scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. The Pt-MWCNT-Nafion nanocomposite film-modified glassy carbon electrode had a sharp hydrogen desorption peak at about -0.2 V vs. Ag/AgCl (3 M) in a solution of 0.5 M H2SO4, which is directly related to the electrochemical activity of the Pt nanoparticles presented on the surface of MWCNTs. The electrocatalytic properties of the Pt-MWCNT-Nafion nanocomposite-modified glassy carbon electrode for methanol electrooxidation were investigated by cyclic voltammetry in a 2 M CH3OH+1 M H2SO4 solution. In comparison with the Pt-coated glassy carbon electrode and the Pt-Nafion modified glassy carbon electrode, the Pt-MWCNT-Nafion-modified electrode had excellent electrocatalytic activity toward methanol electrooxidation. The stability of the Pt-MWCNT-Nafion nanocomposite-modified electrode had also been evaluated.