title: Graphitic biochar as a cathode electrocatalyst support for microbial fuel cells.
abstract: Graphitic biochar (BC) was generated using high temperature gasification and alkaline post-treatment (BCw) of wood-based biomass. The BCw was evaluated as a manganese oxide electrocatalytic support (MnO/BCw) and microbial fuel cell (MFC) air cathode. Nano-structured MnO2 crystals were successfully immobilized on biomass-based graphitic sheets and characterized using physical, chemical, and electrochemical analyses. Cyclic voltammetry of MnO/BCw/Nafion inks showed electrochemical features typical of β-MnO2 with a current density of 0.9 mA cm(-2). BC showed satisfactory maximum power densities of 146.7 mW m(-2) (BCw) and 187.8 W m(-2) (MnO/BCw), compared with Vulcan Carbon (VC) (156.8 mW m(-2)) and manganese oxide VC composites (MnO/VC) (606.1 mW m(-2)). These materials were also tested as oxygen reduction reaction (ORR) catalysts for single chamber MFCs inoculated with anaerobic sludge. Our results demonstrate that BC can serve as an effective, low cost, and scalable material for MFC application.
authors.affiliation: Department of Civil, Environmental, and Architectural Engineering, University of Colorado, Boulder, Boulder, CO 80309, USA; US Naval Research Laboratory, 4555 Overlook Ave. S.W., Code 6100, Washington, DC 20375, USA.
authors.forename: Tyler M
authors.initials: TM
authors.lastname: Huggins
authors.affiliation: US Naval Research Laboratory, 4555 Overlook Ave. S.W., Code 6100, Washington, DC 20375, USA.
authors.forename: Jeremy J
authors.initials: JJ
authors.lastname: Pietron
authors.affiliation: Department of Civil, Environmental, and Architectural Engineering, University of Colorado, Boulder, Boulder, CO 80309, USA.
authors.forename: Heming
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Civil, Environmental, and Architectural Engineering, University of Colorado, Boulder, Boulder, CO 80309, USA.
authors.forename: Zhiyong Jason
authors.initials: ZJ
authors.lastname: Ren
authors.affiliation: US Naval Research Laboratory, 4555 Overlook Ave. S.W., Code 6100, Washington, DC 20375, USA. Electronic address: justin.biffinger@nrl.navy.mil.
authors.forename: Justin C
authors.initials: JC
authors.lastname: Biffinger
mesh_terms: D001674:Bioelectric Energy Sources; D002384:Catalysis; D002606:Charcoal / Q000737:chemistry*; D004560:Electricity; D055664:Electrochemical Techniques; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D012399:Rotation; D013054:Spectrophotometry, Atomic; D013818:Thermogravimetry; D062065:Wastewater / Q000737:chemistry
chemical_list: D002606:Charcoal; D006108:Graphite; D010087:Oxides; D062065:Wastewater; C540010:biochar
keywords: Biochar; Manganese oxide; Microbial fuel cell; O(2) reduction; Renewable