External CO2 and water supplies for enhancing electrical power generation of air-cathode microbial fuel cells
External CO2 and water supplies for enhancing electrical power generation of air-cathode microbial fuel cells
复制标题
用于增强空气阴极微生物燃料电池发电的外部二氧化碳和水供应
DOI：
10.1021/es5021197
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发表时间：
2014
影响因子：
11.4
通讯作者：
S.
中科院分区：
文献类型：
--
作者：
Ishizaki;S.;Fujiki;I.;Sano;D. and Okabe;S.
阴极的碱化限制了空气阴极微生物燃料电池（mfc）的发电能力，因此向阴极提供外部质子是提高发电能力的必要条件。本研究考察了外部co2和水对阴极电极发电的影响，并通过实验计算了co2和水对总质子消耗的相对贡献。二氧化碳的供应降低了阴极pH值，从而增加了发电量。在环境空气条件下，碳酸盐溶解是主要的质子源，为阴极反应提供了约67%的质子消耗。由于碳酸盐的溶解高度依赖于水分含量，因此充分控制空气阴极mfc阴极电极上的水分含量也是至关重要的。在实验结果的基础上，通过向阴极室提供含有50%二氧化碳的潮湿气体，将功率密度提高400%（143.0±3.5 mW/m2）至575.0±36.0 mW/m2。该研究首次证明了同时向阴极电极提供二氧化碳和水可以有效地增加空气阴极mfc的发电量。
Alkalization on the cathode electrode limits the electrical power generation of air-cathode microbial fuel cells (MFCs), and thus external proton supply to the cathode electrode is essential to enhance the electrical power generation. In this study, the effects of external CO2and water supplies to the cathode electrode on the electrical power generation were investigated, and then the relative contributions of CO2and water supplies to the total proton consumption were experimentally evaluated. The CO2supply decreased the cathode pH and consequently increased the power generation. Carbonate dissolution was the main proton source under ambient air conditions, which provides about 67% of total protons consumed for the cathode reaction. It is also critical to adequately control the water content on the cathode electrode of air-cathode MFCs because the carbonate dissolution was highly dependent on water content. On the basis of these experimental results, the power density was increased by 400% (143.0 ± 3.5 mW/m2to 575.0 ± 36.0 mW/m2) by supplying a humid gas containing 50% CO2to the cathode chamber. This study demonstrates that the simultaneous CO2and water supplies to the cathode electrode were effective to increase the electrical power generation of air-cathode MFCs for the first time.