Novel in situ electrochemical deposition of platinum nanoparticles by sinusoidal voltages on conducting polymer films

Platinum (Pt) nanoparticles were successfully electrodeposited in situ on an organic conductive polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), using for the first time sinusoidal voltages of various frequencies in a chloroplatinic acid solution. The organic PEDOT matrix was electrodeposited on Pt electrode chips. The Pt electrode chips consist of a 150 nm Pt layer deposited on 100-oriented standard 3″ silicon wafers. The cyclic voltammograms of the PEDOT–Pt-nanoparticles composite material recorded in 0.5 M H2SO4 aqueous solution demonstrated that Pt nanoparticles are electrochemically active. Values of the roughness of the composite materials, measured by optical non-contact 3D profilometry, ranging from 880 nm to 1.6 μm were obtained depending on the time of deposition of the nanoparticles. The PEDOT–Pt-nanoparticles composite deposited by a sinusoidal voltage with a frequency range of 0.1 Hz–100 kHz, 50 frequencies, has a large specific electrochemical surface area compared with other composite coatings prepared in this work and those previously reported. Atomic force microscopic (AFM) images revealed the presence of numerous deposited Pt nanoparticles on the organic PEDOT polymer film.