title: Enhancement of electricity production by graphene oxide in soil microbial fuel cells and plant microbial fuel cells.
abstract: The effects of graphene oxide (GO) on electricity generation in soil microbial fuel cells (SMFCs) and plant microbial fuel cell (PMFCs) were investigated. GO at concentrations ranging from 0 to 1.9 g⋅kg(-1) was added to soil and reduced for 10 days under anaerobic incubation. All SMFCs (GO-SMFCs) utilizing the soils incubated with GO produced electricity at a greater rate and in higher quantities than the SMFCs which did not contain GO. In fed-batch operations, the overall average electricity generation in GO-SMFCs containing 1.0 g⋅kg(-1) of GO was 40 ± 19 mW⋅m(-2), which was significantly higher than the value of 6.6 ± 8.9 mW⋅m(-2) generated from GO-free SMFCs (p < 0.05). The increase in catalytic current at the oxidative potential was observed by cyclic voltammetry (CV) for GO-SMFC, with the CV curve suggesting the enhancement of electron transfer from oxidation of organic substances in the soil by the reduced form of GO. The GO-containing PMFC also displayed a greater generation of electricity compared to the PMFC with no added GO, with GO-PMFC producing 49 mW⋅m(-2) of electricity after 27 days of operation. Collectively, this study demonstrates that GO added to soil can be microbially reduced in soil, and facilitates electron transfer to the anode in both SMFCs and PMFCs.
authors.affiliation: Electronics-Inspired Interdisciplinary Research Institute (EIIRIS), Toyohashi University of Technology , Toyohashi, Aichi , Japan ; Department of Biomedical Science, College of Life and Health Science, Chubu University , Kasugai, Aichi , Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Goto
authors.affiliation: Electronics-Inspired Interdisciplinary Research Institute (EIIRIS), Toyohashi University of Technology , Toyohashi, Aichi , Japan ; Center for Fostering Young and Innovative Researchers, Nagoya Institute of Technology , Nagoya, Aichi , Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Yoshida
authors.affiliation: Department of Environmental and Life Sciences, Toyohashi University of Technology , Toyohashi, Aichi , Japan.
authors.forename: Yuto
authors.initials: Y
authors.lastname: Umeyama
authors.affiliation: Department of Environmental and Life Sciences, Toyohashi University of Technology , Toyohashi, Aichi , Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yamada
authors.affiliation: Electronics-Inspired Interdisciplinary Research Institute (EIIRIS), Toyohashi University of Technology , Toyohashi, Aichi , Japan ; Department of Environmental and Life Sciences, Toyohashi University of Technology , Toyohashi, Aichi , Japan.
authors.forename: Ryugo
authors.initials: R
authors.lastname: Tero
authors.affiliation: Electronics-Inspired Interdisciplinary Research Institute (EIIRIS), Toyohashi University of Technology , Toyohashi, Aichi , Japan ; Department of Environmental and Life Sciences, Toyohashi University of Technology , Toyohashi, Aichi , Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Hiraishi
keywords: extracellular electron transfer; graphene; graphene oxide; plant microbial fuel cell; soil microbial fuel cell