Effect of Geobacter metallireducens nanowire on electron transfer efficiency in MFC

Abstract

The inhibitory effect of electron mediator 2,6-anthraquinone disulphonate (AQDS) on Geobacter metallireducens nanowire in the microbial fuel cell (MFC) was studied. In the culture process of G.metallireducens with Fe(OH)3 as an electron acceptor, the concentration of reduction product Fe (II) in solution without AQDS was higher than that with AQDS after 10 days, due to the formation of microbial nanowires. The effects of nanowire on electron transfer efficiency and electrical current characteristic were studied using a double chamber MFC reactor. The transfer efficiency between biofilm and electrodes was increased by nanowire, which increased the maximum output voltage of MFC was 442 mV. The nanowire biofilm electrode had a bigger cyclic voltammetry curve peak, smaller activation resistance, and a stronger current response signal through electrochemical measurement, which indicates that the nanowire enhanced the electrochemical activity of the electrode.