One-stage periodical anodic-cathodic double pulse deposition of nanocomposite materials. Application to Prussian Blue/polypyrrole film coated electrodes

Novel electrochemical method of one-stage deposition of composite films on electrode surface has been proposed. The procedure includes a periodical series of potentiostatic or galvanostatic pulses of alternative polarity imposed at electrode in contact with a mixture of two solute precursors, one of which is able to generate a solid phase under its electrooxidation while another one is transformed into another solid phase under its electroreduction. Parameters of anodic and cathodic pulses (potential or current, pulse duration) may be chosen independently from one another, their relation allows one to vary the relative contents of components in the deposited composite. Thickness of the composite film may be regulated by the number of pulses. For illustration this method has been applied for growing films where particles of Prussian Blue are distributed inside polypyrrole matrix. Such modified electrode demonstrates a high catalytic activity and a good stability in the reaction of hydrogen peroxide electroreduction.