Biofilm promoted current generation of Pseudomonas aeruginosa microbial fuel cell via improving the interfacial redox reaction of phenazines

• Published in: Bioelectrochemistry (Amsterdam, Netherlands) Vol. 117; pp. 34 - 39
• Main Authors: Qiao, Ya-Juan, Qiao, Yan, Zou, Long, Wu, Xiao-Shuai, Liu, Jian-Hua
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-10-2017; Elsevier BV
• Subjects: Bacteria; Biochemical fuel cells; Bioelectric Energy Sources - microbiology; Biofilm on anode; Biofilms; Catalysis; Current generation; Electric Conductivity; Electric power generation; Electrochemistry; Electrodes; Electron transfer; Electron Transport; Fuel cells; Fuel technology; Microbial fuel cell; Microorganisms; Phenazine; Phenazine accumulation; Phenazines - metabolism; Pseudomonas aeruginosa; Pseudomonas aeruginosa - metabolism; Pseudomonas aeruginosa - physiology; Sodium; Microbial fuel cell; Pseudomonas aeruginosa; Current generation; Phenazine accumulation; Biofilm on anode
• ISSN: 1567-5394; 1878-562X
• DOI: 10.1016/j.bioelechem.2017.04.003

Bacteria biofilm plays a key role in current generation of microbial fuel cells (MFCs), especially for the start-up stage. However, the detailed mechanism of the biofilm promoting the power generation is not very clear so far, especially for those exoelectrogens who rely on the self-excreted electron mediators for extracellular electron transfer. In this work, a biofilm formation inhibitor—sodium houttuyfonate (SH) is used to build a “non-biofilm” anode of Pseudomonas aeruginosa (P. aeruginosa) without affecting the bacteria growth during the MFC operation. According to the comparison results of the “non-biofilm” anode and biofilm-covered anode on current generation, phenazines concentration variation and anodic electrocatalysis, the biofilm on the anode not only provides plenty of bacterial cells for catalysis but also promotes the interfacial phenazine redox reaction through accumulating the self-generated mediators on anode for fast interfacial electron transfer. This work proves that the biofilm assisted electron mediator accumulation will benefit such kind of exoelectrogens to sustain sufficient electron mediators for extracellular electron transfer.
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•Biofilm formation promotes the current generation of P. aeruginosa anode.•Biofilm assists phenazines accumulation on anode for fast electron transfer.•Phenazines on anode rather than suspended ones determine the anode performance.