纳米材料修饰微生物燃料电池阳极的研究进展

阳极作为微生物燃料电池中的重要组成部分,其性能的高低显著影响着微生物燃料电池的产电性能。纳米材料具有导电性好、表面积大等优良特性。因此,纳米材料修饰阳极能够有效减小电极内阻、增大微生物的粘附量,从而显著提高微生物燃料电池的产电性能。本文首先简要介绍了微生物燃料电池中阳极修饰纳米材料的种类,然后重点归纳了不同纳米材料修饰阳极对微生物燃料电池产电性能的影响及其原因。最后对微生物燃料电池阳极修饰纳米材料和技术进行展望。     

微生物燃料电池中产电微生物的研究进展

产电微生物是微生物燃料电池系统的核心组成, 本文从生物学角度介绍了几种产电微生物的分类学地位、形态特征、生理生化特征及在微生物燃料电池中的产电机理和产电能力, 分析了利用产电微生物进行废水处理同时生物发电的应用前景, 提出产电微生物在MFC系统中的进一步研究方向为微生物的富集、驯化、改造和多种菌种优化组合等。     

产电菌群及电子受体对微生物燃料电池性能的影响

采用2种类型的微生物燃料电池--常规微生物燃料电池(S-MFCs,以生活污水作为产电菌群接种源、以硝酸盐作为电子受体）和改进后的微生物燃料电池（A-MFCs,以厌氧发酵液作为产电菌群接种源、以铁氰化物作为电子受体）,分析了产电菌群和电子受体的改进对微生物燃料电池产电性能的影响.结果表明：产电菌群和电子受体对MFCs驯化周期和运行周期具有显著影响,使驯化周期由S-MFCs的500 h缩短到A-MFCs的430 h,运行周期由S-MFCs的100 h增加到A-MFCs的350 h;改进后的微生物燃料电池使COD去除率提升了25%,使电压输出提高了约300%.选择合适的产电菌菌种和电子受体标准电极电势是微生物燃料电池性能提升的基础.     

微生物燃料电池中产电微生物的研究进展

微生物燃料电池(Microbial fuel cell,MFC)作为一种新型的环境治理和能源技术,目前已得到研究者们的广泛关注。微生物燃料电池是一种利用微生物将有机物中的化学能转化成电能的装置,产电微生物作为生物催化剂,对微生物燃料电池的发展至关重要。不同种类的产电微生物,其电子转移机制与能力有所差异,直接影响MFC的产电性能,从而决定MFC在工程实践中的性能与应用。任何含有大量微生物的废水、污泥、沉积物都可以作为产电微生物的筛选来源,尝试从不同环境条件下分离筛选高效产电微生物有望促进MFC的进一步完善,从而加速其在环境中的应用。通过对微生物燃料电池的发展、产电微生物种类及其电子传递机制等进行总结分析,综述了MFC中产电微生物的最新研究进展,包括产电微生物的筛选方法、种类以及技术研究等,最后展望了今后在产电微生物方面的主要研究方向及MFC的发展前景,以期为产电微生物的的筛选和应用奠定相应的理论基础及提供思路。     

微生物燃料电池中阳极产电微生物的研究进展

微生物燃料电池（MFC）是利用阳极产电微生物为催化剂降解有机废物直接将化学能转化为电能的装置。在MFC系统中,产电微生物是影响产电性能的核心要素之一。介绍了MFC中产电微生物的最新研究现状,详细讨论了产电微生物的种类、产电机理和产电能力．为产电微生物的富集、驯化、改造和多种菌种优化组合提供思路。     

微生物燃料电池阳极产电微生物和阴极受体特性及研究进展

介绍微生物燃料电池的基本工作原理。根据电子传递方式阳极产电微生物分为无需中间体微生物和需中间体微生物。对阴极进行不同反应所涉及的最终电子受体进行了概述,并展望了微生物燃料电池的应用前景。     

一株耐盐产电菌Shewanella algae E-1的分离及其产电特性分析

【背景】产电微生物的种类和电化学活性机制对微生物燃料电池的产电性能有着重要的影响。【目的】从海水中分离获得一株耐盐产电微生物,研究其产电特性并鉴定种属信息。【方法】以取自南海的海水为接种液启动并运行阳极液中含有不同盐浓度的微生物燃料电池,从富集的阳极生物膜上分离得到一株纯培养的微生物菌株,命名为E-1。通过接种于阳极液中添加不同盐浓度的微生物燃料电池中对其产电特性进行分析,并利用形态学观察、Biolog分析和16SrRNA基因序列比对相结合的方法进行种属鉴定。【结果】菌株E-1在无外源添加和外源添加6.6%NaCl条件下产生的功率密度分别为51.69 m W/m2和26.56 m W/m2,这与其良好的耐盐能力相关。菌株E-1被鉴定为海藻希瓦氏菌(Shewanella algae),表现出多样的底物利用能力,生长的温度范围为25-40°C,pH范围为5.0-10.0。【结论】这是首次对Shewanella algae种内微生物产电性能及其在微生物燃料电池中应用的报道,丰富了产电微生物的多样性,菌株E-1能够在较高盐浓度条件下表现出良好的产电性能,为微生物燃料电池在海水资源化处理方面的应用提供新的实验材料。     

微生物燃料电池中假单胞菌F026的产电性能研究

基于微生物燃料电池的反应装置,从污水处理厂曝气池的污泥中通过富集,筛选和基于16S rRNA基因序列的系统发育分析等手段驯化出1株高效产电假单胞菌F026。以F026为阳极产电菌制作微生物燃料电池,考察了底物种类、温度和p H值等因素对微生物燃料电池产电性能的影响。结果表明,F026最适合在以可溶性淀粉为底物,p H为中性偏碱性,温度在30~35℃的环境下生长。在此条件下,微生物燃料电池的最高电压达到500 m V,体积功率密度达到2 W/m3。     

强化产电微生物与电极间电子传递速率的研究进展

产电微生物是微生物燃料电池、电解池和电合成等微生物电化学技术(Microbial electrochemical technologies,METs)的研究基础。产电微生物与电极界面间的胞外电子传递(Extracellular electron transfer,EET)效率低以及生物被膜形成能力弱限制了METs在有机物降解、电能生产、海水淡化、生物修复和生物传感等方面的应用。因此,强化产电微生物与电极界面间的相互作用是过去几年的主要研究热点。针对近年的研究,本文系统概述了通过改造产电微生物来增强微生物-电极间相互作用的各种策略,重点分析了这些策略的适用性和局限性,并展望了强化产电微生物-电极界面作用在微生物电化学技术利用方面的研究前景。     

产电微生物的筛选方法研究进展

产电微生物是一类具有胞外电子转移能力的微生物,能够将有机物中储存的化学能转化为电能,其作为微生物电催化系统的催化剂,已经成为环境和能源领域的研究热点。但目前所发现的产电菌,产电机制有所差异,产电能力参差不齐,菌株的性能从根本上影响了其产电能力,其产电能力不足成为限制微生物燃料电池在工业上广泛应用的主要瓶颈。目前,通过理性设计或定向进化等改造方法,难以实现产电微生物在复杂多样环境中的广泛应用。通过定向筛选策略,建立一套快速、高效的筛选鉴定技术,挖掘环境中性能优异的产电微生物,是促进其广泛应用的有效途径。文中基于产电微生物的种类,总结回顾了现有的产电微生物的筛选鉴定方法,并对其研究前景进行了展望。     

微生物燃料电池在环境污染治理研究中的应用进展

近年来,微生物燃料电池(Microbial fuel cells,MFCs)研究得到了迅速发展。由于可以将可生物降解有机物的化学能直接转化为电能,MFCs在环境污染治理及生物产电方面具有良好的应用前景。本文将全面介绍和总结MFCs在环境污染治理中的研究及应用,其中包括脱氮、脱硫、有机污染物降解、重金属污染治理以及垃圾渗滤液处理等方面。此外,本文还提出MFCs在研究及应用过程中存在的主要问题,并对其研究前景进行展望。     

Enhancement of coulombic efficiency and salt tolerance in microbial fuel cells by graphite/alginate granules immobilization of Shewanella oneidensis MR-1

Coulombic efficiency and stability of electricity output are crucial for practical applications of microbial fuel cells (MFCs). In this study, a cell immobilization method for electrogenic microorganism in MFCs using graphite/alginate granules is developed. The MFC with immobilized cell granules delivered a much more stable electricity output than that with suspension cells, and resulted in a ～0.8 to 1.7 times improvement on coulombic efficiency compared to the suspension mode. Impressively, with the conductive graphite/alginate/cells granules, the internal resistance of the MFC decreased dramatically. Moreover, the cell immobilized MFC showed a much higher tolerance to the shock of high salt concentration than the MFC with suspension cells. The results substantiated that immobilization of electrogenic microorganism for MFCs could be achieved by the method developed here, and it is promising for practical application in energy harvesting from wastewater by MFCs.     

Micro-sized microbial fuel cell: A mini-review

This review presents the development of micro-sized microbial fuel cells (including mL-scale and μL-scale setups), with summarization of their advantageous characteristics, fabrication methods, performances, potential applications and possible future directions. The performance of microbial fuel cells (MFCs) is affected by issues such as mass transport, reaction kinetics and ohmic resistance. These factors are manipulated in micro-sized MFCs using specially allocated electrodes constructed with specified materials having physically or chemically modified surfaces. Both two-chamber and air-breathing cathodes are promising configurations for mL-scale MFCs. However, most of the existing μL-scale MFCs generate significantly lower volumetric power density compared with their mL-counterparts because of the high internal resistance. Although μL-scale MFCs have not yet to provide sufficient power for operating conventional equipment, they show great potential in rapid screening of electrochemically microbes and electrode performance. Additional possible applications and future directions are also provided for the development of micro-sized MFCs.     

Electricity-producing bacterial communities in microbial fuel cells

Microbial fuel cells (MFCs) are not yet commercialized but they show great promise as a method of water treatment and as power sources for environmental sensors. The power produced by these systems is currently limited, primarily by high internal (ohmic) resistance. However, improvements in the system architecture will soon result in power generation that is dependent on the capabilities of the microorganisms. The bacterial communities that develop in these systems show great diversity, ranging from primarily delta-Proteobacteria that predominate in sediment MFCs to communities composed of alpha-, beta-, gamma- or delta-Proteobacteria, Firmicutes and uncharacterized clones in other types of MFCs. Much remains to be discovered about the physiology of these bacteria capable of exocellular electron transfer, collectively defined as a community of "exoelectrogens". Here, we review the microbial communities found in MFCs and the prospects for this emerging bioenergy technology.     

Electrochemical surface modification of carbon mesh anode to improve the performance of air-cathode microbial fuel cells

A convenient and promising alternative to surface modification of carbon mesh anode was fulfilled by electrochemical oxidation in the electrolyte of nitric acid or ammonium nitrate at ambient temperature. It was confirmed that such an anode modification method was low cost and effective not only in improving the efficiency of power generation in microbial fuel cells (MFCs) for synthetic wastewater treatment, but also helping to reduce the period for MFCs start-up. The MFCs with anode modification in electrolyte of nitric acid performed the best, achieving a Coulombic efficiency enhancement of 71 %. As characterized, the electrochemical modification resulted in the decrease of the anode potential and internal resistance but the increase of current response and nitrogen-containing and oxygen-containing functional groups on the carbon surface, which might contribute to the enhancement on the performances of MFCs.     

A novel configuration of microbial fuel cell stack bridged internally through an extra cation exchange membrane

This paper reports a novel configuration of stacked microbial fuel cells (MFCs) bridged internally through an extra cation exchange membrane (CEM). The MFC stack (MFC_stack), assembled from two single MFCs (MFC_single), resulted in double voltage output and half optimal external resistance. COD removal rate was increased from 32.4% to 54.5%. The performance improvement could be attributed to the smaller internal resistance and enhanced cations transfer. A result from a half cell study further confirmed the important role of the extra CEM. This study also demonstrated MFCs where the anode and cathode were sandwiched between two CEMs possessed significantly high power outputs     

Comparison of anode bacterial communities and performance in microbial fuel cells with different electron donors

Microbial fuel cells (MFCs) harness the electrochemical activity of certain microbes for the production of electricity from reduced compounds. Characterizations of MFC anode biofilms have collectively shown very diverse microbial communities, raising ecological questions about competition and community succession within these anode-reducing communities. Three sets of triplicate, two-chamber MFCs inoculated with anaerobic sludge and differing in energy sources (acetate, lactate, and glucose) were operated to explore these questions. Based on 16S rDNA-targeted denaturing gradient gel electrophoresis (DGGE), all anode communities contained sequences closely affiliated with Geobacter sulfurreducens (>99% similarity) and an uncultured bacterium clone in the Bacteroidetes class (99% similarity). Various other Geobacter-like sequences were also enriched in most of the anode biofilms. While the anode communities in replicate reactors for each substrate generally converged to a reproducible community, there were some variations in the relative distribution of these putative anode-reducing Geobacter-like strains. Firmicutes were found only in glucose-fed MFCs, presumably serving the roles of converting complex carbon into simple molecules and scavenging oxygen. The maximum current density in these systems was negatively correlated with internal resistance variations among replicate reactors and, likely, was only minimally affected by anode community differences in these two-chamber MFCs with high internal resistance.     

微生物燃料电池对污染物的强化降解及其机理综述

产电和污染物降解是微生物燃料电池(Microbial Fuel Cells,MFCs)的两个基本功能,也是MFCs作为一种新型的环境治理和能源技术最具吸引力的优势。大量的研究已表明:相对于一般厌氧生物降解技术,MFCs具有更高效的废弃物、废水或污染物降解的能力。解析MFCs强化污染物降解的机理对于进一步优化MFCs的性能具有重要的指导意义,也可以为MFCs在实际环境中的原位应用提供理论支持。本文在综述MFCs强化污染物降解研究报道的基础上,从MFCs中微生物群落的代谢模式、生物膜的活性以及MFCs对局部氧化还原环境的影响等方面为MFCs强化污染物降解的功能提供可能的理论依据,并对MFCs在污染物降解方面的几个可能的发展方向进行展望,为不同学科背景的相关研究者提供参考。     

Microbial fuel cells for energy self-sufficient domestic wastewater treatment—a review and discussion from energetic consideration

As the microbial fuel cell (MFC) technology is getting nearer to practical applications such as wastewater treatment, it is crucial to consider the different aspects that will make this technology viable in the future. In this paper, we provide information about the specifications of an energy self-sufficient MFC system as a basis to extrapolate on the potential benefits and limits of a future MFC-based wastewater treatment plant. We particularly emphasize on the importance of two crucial parameters that characterize an MFC: its electromotive force (E _emf) and its internal resistance (R _int). A numerical projection using state-of-art values (E _emf = 0.8 V and R _int = 5 Ω) emphasized on the difficulty at this moment to reach self-sufficiency using a reasonable number of MFCs at the laboratory scale. We found that a realistic number of MFCs to provide enough voltage (=5 V) at a sufficient current (=0.8 A) to power a pump requiring 4 W would be of 13 MFCs in series and 10 stacks of MFCs in parallel, resulting in a total number of 130 MFCs. That would result in a treatment capacity of 144 L of domestic wastewater (0.5 g-COD L⁻¹) per day. The total MFC system would be characterized by an internal resistance of 6.5 Ω.     

Recent advances in the separators for microbial fuel cells

Separator plays an important role in microbial fuel cells (MFCs). Despite of the rapid development of separators in recent years, there are remaining barriers such as proton transfer limitation and oxygen leakage, which increase the internal resistance and decrease the MFC performance, and thus limit the practical application of MFCs. In this review, various separator materials, including cation exchange membrane, anion exchange membrane, bipolar membrane, microfiltration membrane, ultrafiltration membranes, porous fabrics, glass fibers, J-Cloth and salt bridge, are systematically compared. In addition, recent progresses in separator configuration, especially the development of separator electrode assemblies, are summarized. The advances in separator materials and configurations have opened up new promises to overcome these limitations, but challenges remain for the practical application. Here, an outlook for future development and scaling-up of MFC separators is presented and some suggestions are highlighted.