Characterization of mized-species biofilm established in microbial fuel cells
An MFC operates in the same manner as does a chemical fuel cell,except that in MFCs microbes living as a biofilm on the anode perform the role of anodic catalyst (Aelterman et al.,2006). The biofilm plays a major role in the electrochemical process,and shows marked influence on bioelectricity production (Biffinger et al.,2007; Gemma et al.,2006; Cheng et al.,2008).With the presence of dense cell bodies,a greater portion of cell-to-cell contact is achieved in biofilm which helps to enhance the electron transfer (Picioreanu et al.,2007). Alteration of the composition or structure of the biofilm might influence the electrochemical characteristics and losses of the MFC. Therefore,it is important to understand the characteristic structure and composition of the biofilm to ensure the successful operation of an MFC.In addition,researches into the biofilm benefit to gaining a better understanding of microbial characterization and thus better understand,and perhaps optimize,electron transfer in MFCs. Dual-chambered mediatorless MFCs were set up in order to study the behavior of microbial fuel cells during initial biofilm growth and characterization of mixed species biofilm. Artificial wastewater was used as substrate and anaerobic activated sludge was used as anodic inoculum. After three times of medium replacement,the biofilms were well developed,and the maximum closed circuit potentials at an external resistor of 1000Ω were 0.41 V and 0.37 V,respectively for acetate and glucose as fuel.Electron microscopy revealed that in the biofilm developed in the acetate-fed MFC there were rodshaped cells 0.2-0.3 micrometers wide by 1.5-2.5 micrometers long,and these cells were mainly arranged by monolayer (Fig.1 A). The biofilm in the glucose-fed MFC was made of cocci-shaped cells in chains and a thick matrix (Fig.1B).For both the acetate-fed MFC and glucose-enriched MFC,the bacterial populations of biofilm were different from those of the activated sludge used as inoculum.Cyclic voltammograms suggested that extracellular electron transfer in these MFCs was accomplished mainly by the biofilms on the anode and not by bacteria-produced mediators.
Microbial fuel cell Mized-species biofilm Characterization
Suling Yang H.Liu Fangzhou Du
Laboratory of Environmental Biology and Life Support Technology,School of Biological Science and Medical Engineering,Beihang University,Beijing 100191,China
国际会议
第二届中国微生物燃料电池研讨会(The 2nd Symposium on Microbial Fuel Cell in China)
北京
英文
19-20
2009-11-13（万方平台首次上网日期，不代表论文的发表时间）