Solvent-free electrodeposition of polypyrrole as a base for the preparation of carbonised platinum microelectrodes

The combination of electropolymerisation of suitable monomers and pyrolysis for the local modification of the surface of Pt microelectrodes with pyrolytic carbon films is presented. For use in biological systems, carbon-based electrodes have several advantages over their inert metal counterparts. However, carbon electrodes with dimensions in the sub-μm range lack the required mechanical stability for practical applications. Platinum is employed as a robust support for carbon films to yield carbonised Pt electrodes.Pyrrole, aniline and a polyacrylic resin were investigated for their suitability for forming uniform and stable pyrolytic carbon films on Pt support. Polypyrrole deposited from solvent-free pyrrole (pyrrole concentration higher than 14 M) was found to be most suitable for the formation of stable and crack-free carbon films on Pt electrodes. The carbonised Pt electrodes obtained were characterised electrochemically.