Department of Civil and Environmental Engineering, Penn State University, University Park, PA 16802, USA.
Water Sci Technol. 2011;64(11):2253-8. doi: 10.2166/wst.2011.429.
Tubular cathodes provide a method to obtain high surface areas for scaling up microbial fuel cells (MFCs), but the importance of the cathode shape is not known. We therefore examined power production using cathodes in various configurations (tubes or flat). The MFC with a single internal carbon cloth tube cathode (71 W/m(3)) produced more power than previously obtained with an ultrafiltration membrane (8 W/m(3)) due to the better performance of carbon material. This power density was slightly less than that of a flat carbon cloth cathode (81 W/m(3); 88 m(2)/m(3)) due to the lower total surface area of the tube (68 m(2)/m(3)) and not as a result of the tubular cathode shape. Adding a second tube increased power (83 W/m(3)) in proportion to specific surface area (93 m(2)/m(3)). Wrapping the cathode completely around the anode formed a fully tubular MFC (external tubular reactor) with a higher surface area that produced 128 W/m(3). Volumetric power density was highly correlated with cathode specific surface area (R(2) = 0.93, p = 0.008) and did not depend on the cathode shape (tubes, completely tubular, or flat). Thus, future MFC designs should focus on increasing cathode specific surface area.
管状阴极为扩大微生物燃料电池（MFC）的表面积提供了一种方法，但阴极形状的重要性尚不清楚。因此，我们研究了使用各种构型（管或平板）的阴极的产电功率。由于碳材料性能更好，具有单个内部碳布管阴极（71 W/m³）的 MFC 产生的功率比以前使用超滤膜（8 W/m³）获得的功率更大。由于管的总表面积较小（68 m²/m³），而不是由于管状阴极形状，因此该功率密度略低于平板碳布阴极（81 W/m³；88 m²/m³）。增加第二个管会使功率成比例增加（83 W/m³），这与比表面积成正比（93 m²/m³）。将阴极完全包裹在阳极周围形成了具有更高表面积的全管状 MFC（外部管状反应器），其产生的功率为 128 W/m³。体积功率密度与阴极比表面积高度相关（R²=0.93，p=0.008），而不取决于阴极形状（管、全管状或平板）。因此，未来的 MFC 设计应侧重于增加阴极比表面积。
