title: Electrochemical and impedance characterization of Microbial Fuel Cells based on 2D and 3D anodic electrodes working with seawater microorganisms under continuous operation.
abstract: A mixed microbial population naturally presents in seawater was used as active anodic biofilm of two Microbial Fuel Cells (MFCs), employing either a 2D commercial carbon felt or 3D carbon-coated Berl saddles as anode electrodes, with the aim to compare their electrochemical behavior under continuous operation. After an initial increase of the maximum power density, the felt-based cell reduced its performance at 5 months (from 7 to 4 μW cm(-2)), while the saddle-based MFC exceeds 9 μW cm(-2) (after 2 months) and maintained such performance for all the tests. Electrochemical impedance spectroscopy was used to identify the MFCs controlling losses and indicates that the mass-transport limitations at the biofilm-electrolyte interface have the main contribution (>95%) to their internal resistance. The activation resistance was one order of magnitude lower with the Berl saddles than with carbon felt, suggesting an enhanced charge-transfer in the high surface-area 3D electrode, due to an increase in bacteria population growth.
authors.affiliation: Center for Space Human Robotics @PoliTO, Istituto Italiano di Tecnologia, C.so Trento 21, 10129 Torino, Italy; Applied Science and Technology Department, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Hidalgo
authors.affiliation: Center for Space Human Robotics @PoliTO, Istituto Italiano di Tecnologia, C.so Trento 21, 10129 Torino, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Sacco
authors.affiliation: Center for Space Human Robotics @PoliTO, Istituto Italiano di Tecnologia, C.so Trento 21, 10129 Torino, Italy; Applied Science and Technology Department, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Hernández
authors.affiliation: Center for Space Human Robotics @PoliTO, Istituto Italiano di Tecnologia, C.so Trento 21, 10129 Torino, Italy. Electronic address: tonia.tommasi@iit.it.
authors.forename: T
authors.initials: T
authors.lastname: Tommasi
mesh_terms: D001674:Bioelectric Energy Sources / Q000382:microbiology*; D058266:Dielectric Spectroscopy; D017097:Electric Impedance; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D012623:Seawater / Q000382:microbiology*
keywords: 3D electrode; Carbon-coated Berl saddles; Electrochemical impedance spectroscopy; Enriched seawater inoculum; Microbial Fuel Cell