Pulse electropolymerization synthesis of PPy(DBS) nanoparticle layers

International audienceA one-step process using a pulse electropolymerization technique is used to fabricate nanoparticles of polypyrrole (PPy) with dodecyl benzene sulfonate (DBS) anions from an aqueous solution without template and without using any chemical additives. The morphology of particles is controlled by changing the pulse duration (from 120 to 0.5 s), while keeping the relaxation time constant at 15 s. Short pulses resulted in the formation of PPy(DBS) nanoparticles with an average particle size of about 50 nm. The control of the size of the PPy(DBS) nanoparticles is ascribed to a pulse electropolymerization growth mechanism, whereby progressive nucleation associated with two-dimensional growth is initiated at each new pulse cycle from the equilibrium electrolyte solution. Short pulses are needed to avoid nonuniform growth of nanoparticles and control the particle size. Sufficiently long relaxation time is required to restore the equilibrium concentrations in the vicinity of the working electrode by suppressing the double layer. Combining short pulses with sufficiently long relaxation times enables the formation of PPy(DBS) nanoparticles. The proposed short-pulse technique is meant to be applied to the fabrication of a wide range of nanostructured conductive polymers