Exploring the use of 3 dimensional low-cost sugar-urea carbon foam electrode in the benthic microbial fuel cell

Abstract

Benthic microbial fuel cell (BMFC) produces electrical energy due to the redox gradient between anode and cathode. Exoelectrogens present at anode consume organic substrates and produce electrons. Anode act as an electron acceptor, therefore, requires efficient material for power enhancement in BMFC. 3D Carbon foam was synthesized as anode material by slow heating of table sugar and urea foam until 900 °C in presence of Nitrogen gas. Cost-efficient 3D Sugar-Urea Carbon Foam electrode material was decorated over steel wool named as SUF. Magnetite was added at the initial step to prepare Magnetite doped Carbon foam named as SUMF. Composite electrode materials were used in lab-scale BMFC and compared with Carbon felt (C). These composites were characterized by Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Chronocoulomerty (CC), Cyclic voltammetry (CV), and Electrochemical impedance spectrometry (EIS). ImageJ was used for the determination of pore area percentage and pore size from SEM images. Exchange current density calculated for C, SUF, and SUMF was 0.09, 3.51, and 0.18 A m−2 respectively. Maximum power achieved was 0.27, 3.5, and 2.6 mW and their corresponding power densities were 8.5, 190, and 67 mW m−2 for C, SUF, and SUMF respectively. Synthesized 3D electrode material showed better performance compared to carbon felt due to enhanced surface area and biocompatibility.