Optimizing the electrode surface area of sediment microbial fuel cells

Abstract

Sediment microbial fuel cells (SMFCs) is a promising technology for bioremediation, environmental monitoring and remote power supply in various water environments. Optimizing the anode/cathode surface area ratio (SAR a/c ) is important to enhance the power and decrease the cost of SMFCs. However, in fact, little information has been reported to optimize the SAR a/c of SMFCs in individual or stacked mode. This study comparatively analyzed the effects of electrode surface areas on the performance of single SMFCs and serial SMFC-stacks under separated- and connected-hydraulic conditions. The results suggested an optimal SAR a/c of 1 to 1.33 for both single and serial stacked SMFCs. Voltage reversal occurred in serial SMFC stacks with unoptimal SAR a/c but not in optimized stacks. The more the SAR a/c deviated from the optimal SAR a/c , the more easily the voltage reversal occurred ( i.e. lower reversal current). Compared to a separated-hydraulic environment, a connected-hydraulic environment showed no effect on the power generation of anode-limiting SMFC stacks but decreased the power generation and reversal current of cathode-limiting SMFCs, probably due to larger parasitic current. The results are important for the scale-up and application of SMFCs.

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Identifiers

DOI

10.1039/c8ra05069d

Journal

RSC Advances

Year

2018