Carbon nanotube/chitosan nanocomposite as a biocompatible biocathode material to enhance the electricity generation of a microbial fuel cell

New developments in biocathode microbial fuel cells (MFCs) provide an increasing possibility to use the MFC technology for sustainable wastewater treatment. Enhanced oxygen reduction and biofilm formation using novel cathode materials are crucial for the biocathode MFCs. Here we report the use of a conductive and compatible carbon nanotube/chitosan nanocomposite as a new type of MFC biocathode material, which is fabricated by electrodepositing carbon nanotubes and chitosan onto a carbon paper electrode. The MFC tests reveal that the electricity generation capacity of this nanocomposite anode is superior to the control. The electricity generation and the maximum power density of the MFC with this nanocomposite increase by 67% and 130%, respectively, compared with the MFC with carbon paper biocathode. This result demonstrates that the use of such a nanocomposite offers an effective means to enhance the electricity generation of biocathode MFCs. This approach is applicable for the development of other types of materials for MFC cathodes through facilitating the electron transfer at the electrode/bacteria interface.