Three-dimensional macroporous CNT-SnO2 composite monolith for electricity generation and energy storage in microbial fuel cells

A facile electrophoretic deposition method was used to prepare a three- dimensional macroporous CNT-SnO2 monolith as a MFC anode. This 3D CNT-SnO2 composite presents a clear micro-structure with CNTs inside and amorphous SnO2 nanoparticles coating the CNT surface, and has both good electricity generation and energy storage in MFCs. Experimental results show that the CNT-SnO2 composite possesses good biocompatibility and improved electrical conductivity. Compared with CNT, CNT-SnO2 presents a much higher output current density (2.21 versus 0.47 mA cm(-2)) and power density (673.5 versus 443.1 mW m(-2)). The discharge-charge experiments show that the CNT-SnO2 composite has a greater specific capacitance than the CNT electrode (382 versus 42.8 mF cm(-2)) with a discharge-charge current density of 1 mA cm(-2). These results reveal that the 3D CNT-SnO2 composite has great promise as the anode material for MFCs.