Electrochemical Synthesis of an Organometallic Material Based on Polypyrrole/MnO2 as High-Performance Cathode

International audienceWe report herein the design ofpromising composite material as a cathode in a rechargeable battery by combining the properties of polypyrrole (PPy) and MnO2 particles.The compositeswerepreparedbyelectropolymerization of the pyrrole monomer followed by electrodeposition of a manganese salt suspension bytwo methods.The first method involved the formation of MnO2in situ in the PPy/ITO electrode, while the second method involved first a preliminary adsorption of Mn2+ions in the polymer, followed by anelectrochemical ofthe electrode. Themorphology of the resulting composite materials (PPy/MnO2) was studied by Energy-dispersive X-ray spectroscopy (EDS), X-ray diffractometry (XRD), scanning electron microscopy (SEM),Fourier-transform infrared (FTIR).The investigations of the electrochemical properties of the compositeelectrodes show thatthe presenceof MnO2play an important role in improving the surfaceof polymer films, which leads to lower charge transfer resistance and higher electrode activity.Forthe optimal synthesismethod, the electrode generates a maximum current of up to -7.9 mA.cm-2for the oxygen reduction reaction, which is eight times the current density delivered by the electrode without PPy