Liu Liang, Li Fang-bai, Feng Chun-hua, Li Xiang-zhong
Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
Appl Microbiol Biotechnol. 2009 Nov;85(1):175-83. doi: 10.1007/s00253-009-2147-9. Epub 2009 Aug 1.
Microbial fuel cells (MFCs) were constructed using azo dyes as the cathode oxidants to accept the electrons produced from the respiration of Klebsiella pneumoniae strain L17 in the anode. Experimental results showed that a methyl orange (MO)-feeding MFC produced a comparable performance against that of an air-based one at pH 3.0 and that azo dyes including MO, Orange I, and Orange II could be successfully degraded in such cathodes. The reaction rate constant (k) of azo dye reduction was positively correlated with the power output which was highly dependent on the catholyte pH and the dye molecular structure. When pH was varied from 3.0 to 9.0, the k value in relation to MO degradation decreased from 0.298 to 0.016 micromol min(-1), and the maximum power density decreased from 34.77 to 1.51 mW m(-2). The performances of the MFC fed with different azo dyes can be ranked from good to poor as MO>Orange I>Orange II. Furthermore, the cyclic voltammograms of azo dyes disclosed that the pH and the dye structure determined their redox potentials. A higher redox potential corresponded to a higher reaction rate.
使用偶氮染料作为阴极氧化剂构建微生物燃料电池（MFC），以接受肺炎克雷伯菌L17菌株在阳极呼吸产生的电子。实验结果表明，在pH 3.0时，以甲基橙（MO）为燃料的MFC与以空气为氧化剂的MFC性能相当，并且包括MO、橙黄I和橙黄II在内的偶氮染料能够在这种阴极中成功降解。偶氮染料还原的反应速率常数（k）与功率输出呈正相关，功率输出高度依赖于阴极电解液的pH值和染料分子结构。当pH值从3.0变化到9.0时，与MO降解相关的k值从0.298降至0.016 μmol min⁻¹，最大功率密度从34.77降至1.51 mW m⁻²。以不同偶氮染料为燃料的MFC性能从优到差依次为MO＞橙黄I＞橙黄II。此外，偶氮染料的循环伏安图表明，pH值和染料结构决定了它们的氧化还原电位。较高的氧化还原电位对应较高的反应速率。
