Modification of graphite felt using nano polypyrrole and polythiophene for microbial fuel cell applications-a comparative study

Microbial fuel cells (MFC) are bio-electrochemical devices used for the generation of electricity from biomass. A single chamber membrane less air-breathing cathode microbial fuel cell (SCMFC) with two different anode configurations was investigated for energy generation using shewanella putrifaciens as bio-catalyst. The graphite felt (GF) anode was modified with 0.008 g/cc polypyrrole nanoparticles (Ppy-NPs) and 0.024 g/cc polythiophene nanoparticles (PTh-NPs) by conventional method. The nanoparticles coating improved the properties such as thermal characteristics and electron transfer capabilities of the anodes, which was confirmed by Thermogravimetric analysis (TGA), electrochemical impedance spectroscopy (EIS) and cyclic voltametry (CV). The variation in the cell potential with time under open circuit condition resulted in voltages of 0.842V and 0.644 V for Ppy-NP and PTh-NP modified GF respectively. A maximum power density (1.22 W/m²) was obtained for Ppy-NP modified GF than PTh-NP modified GF (0.8 W/m²). The results showed that GF coated with nano conductive polymers such as Ppy and PTh are the promising candidates for the best performance of a MFC.