TITLE:
Sizes of Anode and Cathode Affect Electricity Generation in Rice Paddy-Field Microbial Fuel Cells
AUTHORS:
Nagayoshi Ueoka, Naoko Sese, Mayu Sue, Atsushi Kouzuma, Kazuya Watanabe
KEYWORDS:
Root Exudates, Polarization Analyses, Pyrosequencing, 16S rRNA Gene, Geobacter
JOURNAL NAME:
Journal of Sustainable Bioenergy Systems,
Vol.6 No.1,
March
17,
2016
ABSTRACT: Rice paddy-field microbial fuel cells (RPF-MFCs) are devices that exploit rhizosphere bacteria to
generate electricity from soil organic matter, including those excreted from roots. Previous studies
have examined factors affecting electric outputs from RPF-MFCs and demonstrated that RPFMFC
was able to generate electricity up to 80 mW·m-2 (based on the projected area of anode). The
present study operated RPF-MFCs with different sizes of anodes and cathodes and examined how
electrode sizes affected electricity generation. We show that anodes are the limiting factor for
electricity generation immediately after commencing the operation, while cathodes become the
limiting factor after anode performances are sufficiently increased. RPF-MFC achieved the maximum
power density of 140 mW·m-2 (based on the projected area of anode), when the cathode is
sufficiently larger than the anode. Results suggest that the cathode needs to be improved for eliciting
the maximum capacity of rhizosphere bacteria for electricity generation in RPF-MFC.