Effect of zeolite-coated anode on the performance of microbial fuel cells

BACKGROUND: For a microbial fuel cell (MFC), the anode material plays a key part in power generation. Modification of conventional carbon-based anode materials is an effective strategy to improve MFC performance. RESULTS: Two different zeolites, namely, mobil catalytic materials number 41 (MCM-41) and NaX, were used to modify graphite felt anodes and compared with unmodified anodes in dual-chamber MFCs. Fourier transform infrared analysis verified that MCM-41 and NaX zeolites were successfully coated onto the bare graphite felt surface. Results showed that NaX zeolite is a favorable, affordable material for anode modification of MFCs. This zeolite improved MFC performance considerably. Its maximum power density (215.3±6.4mW m^-2) and CE value (50.0%±2.0%) were 152.1% and 36.2% higher than those of the unmodified anode, respectively. According to scanning electron microscopy, cyclic voltammetry, and the amount of anode biomass, the superhydrophilicity of the NaX zeolite-modified anode was a vital reason for thick anode biofilm formation and accelerated anodic bio-electrochemical reactions. The improved specific surface area of the anode and properties of the microporous NaX zeolite were responsible for the enhancement of MFC performance. CONCLUSIONS: Graphite felt anode modified by NaX zeolite resulted in improved power generation by a MFC.