A Ti/TiO2-polyaniline (PAni) composite electrode was developed and explored with electrochemical methods. The results of electrochemical impedance spectroscopy (EIS) demonstrate that under abiotic conditions the cathode is the limiting component of the electrochemical cell for the occurrence of the charge-transfer reactions. In contrast, when the Ti/TiO2-PAni composite is working as anode in the microbial fuel cells (MFCs) studied, the controlling electrochemical processes occur at the anode. The higher power densities, 2317 mW/m², were obtained with a pure culture of Geobacter sulfurreducens, and significant power density was obtained with an uncharacterized consortium, 1137 mW/m². The results showed that the Ti/TiO2-PAni anode is a suitable material to be optimized for developing highpower MFCs with G. sulfurreducens for wastewater treatment.
microbial fuel cell (MFC), polyaniline (PAni), impedance spectroscopy (EIS), Geobacter sulfurreducens
Dr. Bernard Tribollet (Laboratoire Interfaces et Systemes Electrochimiques, LISE - UPR15 du CNRS, Université Pierre et Marie Curie, France) is specially acknowledged for the technical assistance on impedance spectroscopy. We are also thankful to Professor Derek Lovley (Geobacter Project, Environmental Biotechnology Center, UMass/Amherst,USA), for donating the Geobacter sulfurreducens strain used for this investigation. We also express our gratitude to Dr. Ulises Morales-Ortiz (Departamento de Química, Área Electroquímica, UAM Iztapalapa, Mexico), for providing the Ti coupons.
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