Investigation of Pulse-Electropolymerization of Conductive Polypyrrole Nanostructures

We report here the electrochemical polymerization of polypyrrole (PPy) on platinum substrates by pulse galvanostatic method. The effects of variables as pulse height (current amplitude), relaxation time (toff), pulse time (ton), bath temperature, HCl and pyrrole concentrations were studied using SEM, UV-vis spectroscopy, Cyclic Voltammetry, and conductivity. The obtained results reveal the morphology and particles sizes of polypyrrole samples were strongly depended on the synthesis conditions. By changing the synthesis conditions, we can prepare nanoparticles, nanorods, nanoporous moss and nanotubes. The sample including nanotubes with 145 nm average outer diameter, 80 nm average inner diameter and 1600 nm average length selected as the best sample which can be synthesized on the conditions including 9 mA cm-2 current density, 1 s relaxation time, 1 s pulse time, 30 °C solution temperature, 0.1 M pyrrole and 0.12 M HCl.