Microbial biofuel cell operating effectively through carbon nanotube blended with gold-titania nanocomposites modified electrode

In this study, we have explored the possibility to fabricate microbial biofuel cell operating with carbon nanotube-gold-titania nanocomposites (CNT/Au/TiO2) as anode modifier. The results demonstrate that the CNT/Au/TiO2 electrode could be utilized as a new and effective microbial fuel cell (MFC) anode, which integrate the advantages of relevant nanocomposites such as high conductivity, high specific surface area, and easy adsorption of the microorganism. It is evident that the three-dimensional network nanostructures of CNT/Au/TiO2 are propitious to improve the relevant anode surface area and thus the adsorption of the microorganism, which can efficiently promote the electronic transfer rate between the probe and electrode. Meanwhile, it is noted that open circuit voltage of the CNT/Au/TiO2 nanocomposites modified carbon paper anode increased to 0.77 V, which is more than twice that of the open circuit voltage obtained with bare carbon paper anode (0.36 V). And the MFC equipped with CNT/Au/TiO2 nanocomposites modified carbon paper anode delivers a maximum power density of 2.4 mW m−2, which is three times larger than that obtained from the MFC with bare carbon paper. This observation illustrates that the CNT/Au/TiO2 nanocomposites modified electrode could obviously increase the relevant electron transfer rate and promote the electron exchange at electrode surface, which could readily provide enhanced stability and relatively long life-span to facilitate the high electricity production efficiency, suggesting its promising prospect application in MFCs.