ABSTRACT
The low sensitivity of microbial fuel cell ( MFC)-biosensor is one of the bottlenecks in its practical application. To investigate the effect of anode electrode modified with carbon nanomaterials on the sensitivity of water toxicity detection of MFC-based biosensor, graphite felts ( GF ) were modified using two carbon nanomaterials of multi-walled carbon nanotubes ( MWNT ) and conductive carbon black ( GCB ) . MFC biosensors were started up with the anode electrodes, and the results showed that resistance of the GCB and MWNT-modified electrode was smaller than that of unmodified electrode, and the order of MFC power output was GCB/GF-MFC (2. 63 W/m2)>MWNT/GF-MFC (2. 56 W/m2)>GF-MFC (2. 09 W/m2). Then, 3, 5-dichlorophenol poison ( DCP) was used as a model toxicant in toxicity test, the order of toxicity inhibition ratios of 10 mg/L DCP to three MFC biosensor was MWNT/GF-MFC (31. 8% )>GCB/GF-MFC (26. 3% )>GF-MFC (20. 1% ). The sensitivity for toxicity detection by MFC biosensors with anode electrode modified with carbon nanomaterials was improved, and MWNT/GF-MFC had the highest sensitivity. The result of the study may promote the application of MFC biosensor in water pollution monitoring.