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 b-MnO2 with a current density of 0.9 mA cm2. BC showed satisfactory maximum power densities of
146.7mWm2 (BCw) and 187.8Wm2 (MnO/BCw), compared with Vulcan Carbon (VC)
(156.8mWm2) and manganese oxide VC composites (MnO/VC) (606.1mWm2). 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.