BACKGROUNDFor 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. RESULTSTwo 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 (215.36.4mW 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. (c) 2013 Society of Chemical Industry