Abstract: A new type of single-chamber direct microbial fuel cell was constructed successfully on the basis of studying the cathode electrode containing Fe3+. The electricity generation mechanism of the single-chamber microbial fuel cell and the effect of different Fe3+contents on cell voltage in the cathode electrode were studied through experiments. By analyzing the cell voltage measured by the acquisition system, it is proved that the single-chamber direct microbial fuel cell is feasible, microbial electricity generation is mainly attributed to the electrochemically and biologically active cells attached to the electrode. The use of an Fe3+-graphite cathode enhanced the oxidation-reduction efficiency. Electron transfer driving force was generated in coupling of Fe3+ reduction to Fe2+ on the cathode. The Fe2+ cations were subsequently oxidized by O2 in air. For this Fe3+ circular effect, the electron transfer and oxidation-reduction efficiency were enhanced. The power density of the single direct microbial fuel cell was up to 14.58 mW/m2.

Key words: single-chamber direct microbial fuel cell, biofilm, cathode electrode, Fe3+ circular transform

摘要： 在研制含铁离子阴极电极板的基础上，构建了单室直接微生物燃料电池. 通过实验考察了单室无介体微生物燃料电池的产电规律及阴极板中铁离子含量对产电的影响. 实验证明，单室直接微生物燃料电池是可行的，电能的输出主要依赖吸附在电极表面的细菌形成的生物膜，而与悬浮在溶液中的细菌及溶液中的其他物质基本无关. 在单室无介体微生物燃料电池的阴极板中添加铁离子，通过铁离子在二价和三价间的循环转化，提高了电子的传递速率，加快了质子和氧气的反应，电池的输出功率达到14.58 mW/m2.

关键词: 单室无介体微生物燃料电池, 生物膜, 阴极电极, 铁离子循环转化