Polydopamine as a new modification material to accelerate startup and promote anode performance in microbial fuel cells

• Published in: Journal of power sources 2017-03, Vol.343, p.477-482
• Main Authors: Du, Qing, An, Jingkun, Li, Junhui, Zhou, Lean, Li, Nan, Wang, Xin
• Format: Article
• Language: English
• Subjects: Activated carbon; Bioelectrochemical systems; Microbial fuel cells; Polydopamine
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2017.01.093

The bacterial anode material is important to the performance of microbial fuel cells (MFCs) because its characteristics affect the biofilm formation and extracellular electron transfer. Here we find that a superhydrophilic semiconductor, polydopamine (PDA), is an effective modification material for the anode to accelerate startup and improve power density. When the activated carbon anode is added with 50% (wt.) PDA, the startup time is 14% shorter than the control (from 88 h to 76 h), with a 31% increase in maximum power density from 613 ± 9 to 803 ± 6 mW m−2, and the Columbic efficiency increases from 19% to 48%. These can be primarily attributed to the abundant functional groups (such as amino group, and catechol functions) introduced by PDA that improve hydrophilicity and extracellular electron transfer. PDA also increases proportions of Proteobacteria and Firmicutes families, indicating that PDA has a selective effect on anode microbial community. Our findings provide a new approach to accelerate anode biofilm formation and enhance MFC power output by modification of biocompatible PDA. [Display omitted] •Polydopamine (PDA) modification accelerates the startup of MFC anode.•50% PDA content in the anode increases MFC power density by 31%.•The Coulombic efficiencies also increased from 19% to 48%.•The increase can be attributed to the abundant functional groups introduced by PDA.•The superhydrophilic PDA imposed selective pressure on anode microbial community.