Effect of anode aeration on the performance and microbial community of an air-cathode microbial fuel cell

An air-cathode microbial fuel cell (MFC), previously enriched under anode anaerobic conditions, was exposed to air intermittently and continuously, to investigate the effects of anode aeration on power generation and microbial community. Intermittent aeration had little influence on power generation except reduction in coulombic efficiency (CE). During continuous anode aeration lasting 420 h, a considerable amount of electricity with a voltage of 0.35-0.41 V (1000 Omega external resistor) was produced within a wide range of dissolved oxygen concentrations (0.1-4.0 mg/L). Anode aeration influenced maximum voltage output less, but reduced CE significantly. The MFC reclaimed previous power generation ability soon after aeration stopped. Aeration caused a decline in anode microbial diversity compared to the anaerobic control with Burkholderia sp., Bacteroidetes sp., Simplicispira sp., Rhodocyclaceae sp., and Microbacterium sp. being the dominant members. The air-cathode MFC enriched under anaerobic conditions showed a good resistance to oxygen and demonstrated the potential to generate electricity under anoxic and aerobic conditions. (C) 2012 Elsevier B.V. All rights reserved.