Pt-supported air-cathodes still need improvement if their application in MFC technology is to be sustainable. In this context, the efficiency of an air-cathode was studied with respect to the pH of the solution it was exposed to. Voltammetry showed that oxygen reduction was no longer limited by H+ availability for pH lower than 3.0. A new MFC was designed with a catholyte compartment setup between the anode compartment and the air-cathode. With a catholyte compartment at pH 1.0, the MFC provided up to 5 W/m2, i.e., 2.5-fold the power density obtained with the same anode and cathode in a single-chamber MFC working at pH 7.5. Current density exceeded 20 A/m2. The benefit of low-pH in the catholyte chamber largely counterbalanced the mass transfer hindrance due the membrane that separated the two compartments. The MFC kept 66% its performance during nine days of continuous operation.
展开▼
机译：如果要使Pt支撑的空气阴极在MFC技术中的应用可持续发展，仍需要改进。在这种情况下，相对于其暴露于溶液的pH，研究了空气阴极的效率。伏安法表明，对于pH值低于3.0的情况，氧的还原不再受H +可用性的限制。设计了一种新的MFC，在阳极室和空气阴极之间设置了阴极室。在pH值为1.0的阴极电解液室中，MFC可提供高达5 W / m2的能量，即在pH 7.5的单室MFC中使用相同的阳极和阴极获得的功率密度的2.5倍。电流密度超过20 A / m2。阴极液室中低pH值的好处在很大程度上抵消了由于分隔两个隔室的膜而引起的传质障碍。在连续运行9天中，MFC的性能保持了66％。
展开▼
