title: Membrane-less cloth cathode assembly (CCA) for scalable microbial fuel cells.
abstract: One of the main challenges for scaling up microbial fuel cell (MFC) technologies is developing low-cost cathode architectures that can generate high power output. This study developed a simple method to convert non-conductive material (canvas cloth) into an electrically conductive and catalytically active cloth cathode assembly (CCA) in one step. The membrane-less CCA was simply constructed by coating the cloth with conductive paint (nickel-based or graphite-based) and non-precious metal catalyst (MnO(2)). Under the fed-batch mode, the tubular air-chamber MFCs equipped with Ni-CCA and graphite-CCA generated the maximum power densities of 86.03 and 24.67 mW m(-2) (normalized to the projected cathode surface area), or 9.87 and 2.83 W m(-3) (normalized to the reactor liquid volume), respectively. The higher power output of Ni-CCA-MFC was associated with the lower volume resistivity of Ni-CCA (1.35 x 10(-2)Omega cm) than that of graphite-CCA (225 x 10(-2)Omega cm). At an external resistance of 100 Omega, Ni-CCA-MFC and graphite-CCA-MFC removed approximately 95% COD in brewery wastewater within 13 and 18d, and achieved coulombic efficiencies of 30.2% and 19.5%, respectively. The accumulated net water loss through the cloth by electro-osmotic drag exhibited a linear correlation (R(2)=0.999) with produced coulombs. With a comparable power production, such CCAs only cost less than 5% of the previously reported membrane cathode assembly. The new cathode configuration here is a mechanically durable, economical system for MFC scalability.
authors: Guangdong Institute of Eco-environmental and Soil Sciences, 808 Tianyuan Road, Guangzhou, Guangdong Province 510650, China.
authors: Li
authors: L
authors: Zhuang
authors: Shungui
authors: S
authors: Zhou
authors: Yueqiang
authors: Y
authors: Wang
authors: Chengshuai
authors: C
authors: Liu
authors: Shu
authors: S
authors: Geng
mesh_terms: D001674:Bioelectric Energy Sources / Q000382:microbiology*; D004563:Electrochemistry / Q000295:instrumentation*; D004566:Electrodes; D004581:Electronics / Q000295:instrumentation*; D008567:Membranes, Artificial
chemical_list: D008567:Membranes, Artificial