Microbial fuels

Liu L, Li F-b, Feng CF1 (2009) Microbial fuel cell with an azo-dye-feeding cathode. Appl Microbiol Technol 85 175-183... 

Fuel cell applications Manganese dioxide as a new cathode catalyst in microbial fuel cells [118] OMS-2 catalysts in proton exchange membrane fuel cell applications [119] An improved cathode for alkaline fuel cells [120] Nanostructured manganese oxide as a cathodic catalyst for enhanced oxygen reduction in a microbial fuel cell [121] Carbon-supported tetragonal MnOOH catalysts for oxygen reduction reaction in alkaline media [122]... 

Manganese dioxide as a new cathode catalyst in microbial fuel cells. Journal of Power Sources, 195, 2586-2591. 

Some new developments are also proposed such as a system based on the use of electrochemically active bacteria in combination with a microbial fuel cell [34], giving good responses over 60 days, or a biosensor developed for fast... 

The so-called microbial fuel cells (MFC) are a completely different type of fuel cell. Here, bacteria are used to convert a bio-usable substrate directly into electricity. In the future, it might be possible to run an MFC for medical purposes by using glucose directly from the patient s bloodstream (Logan et al., 2006). 

Microbial biofuel cells were the earliest biofuel cell technology to be developed, as an alternative to conventional fuel cell technology. The concept and performance of several microbial biofuel cells have been summarized in recent review chapters." The most fuel-efficient way of utilizing complex fuels, such as carbohydrates, is by using microbial biofuel cells where the oxidation process involves a cascade of enzyme-catalyzed reactions. The two classical methods of operating the microbial fuel cells are (1) utilization of the electroactive metabolite produced by the fermentation of the fuel substrate " and (2) use of redox mediators to shuttle electrons from the metabolic pathway of the microorganism to the electrodes. ... 

Recently, a novel microbial fuel cell harvesting energy from the marine sediment—seawater interface has been reported. Also, a novel photosynthetic biofuel cell that is a hybrid between a microbial and enzymatic biofuel cell has been reported for the very first time. More recently, reports of an unconventional biomass-fueled ceramic fuel cell can also be found in the literature. A new concept of Gastrobots —hybrid robots that utilize operational power derived from microbial fuel cells—has been introduced. Finally, the generation of electrical power by direct oxidation of glucose was demonstrated in mediatorless microbial fuel cells, which produced currents up to 3 fiA/cm at unknown cell voltage. ... 

Biofuel cells — also referred to as biochemical, or bio-electrochemical fuel cells, exploit biocatalysts for the direct conversion of chemical energy to electrical energy. Based on the nature of the biocatalyst, biofuel cells are generally classified as enzymatic fuel cells and microbial fuel cells [i]. Enzymatic fuel cells use purified enzymes to catalyze the oxidation of substrates at the - anode and... 

In microbial fuel cells living microorganisms serve as bio catalysts for the conversion of chemical energy to electricity. Since the majority of microorganisms are electrochemically inactive some early microbial fuel cells required the use of artificial electron-shuttling com-... 

Biofuel cells — Figure. Schematic illustration of identified electron transfer mechanisms in microbial fuel cells. Electron transfer via (a) cell membrane-bound cytochromes, (b) electrically conductive pili (nanowires), (c) microbial redox mediators, and (d) via oxidation of reduced secondary metabolites [v]... 

FIGURE 2.3 Power Generation with Microbial Fuel Cells. SOURCE Presentation of Judy Raper, National Science Foundation used with permission from Bruce Logan, Pennsylvania State University. 

Palmore also talked about examples of microbial systems. Derek Lovley s laboratory at University of Massachusetts, Amherst, is looking at doing electrochemistry in ocean or bay sediments. New organisms are being discovered through their research and the use of a microbial fuel cell in which carbohydrates are taken to carbon dioxide using Rhodoferax ferrireducens have been demonstrated. 

Chaudhuri, S., Lovley, D. (2003). Electricity generation by direct oxidation of glucose in mediatorless microbial fuel cells. Nature Biotechnology 21,1229-1232. 

The only deviation from this pattern is the DMFC (direct methanol fuel cell) which uses methanol as a fuel without intermediate reforming and microbial fuel cells that use sugar as a fuel and derive current from the metabolic activity of yeast. Both types use a solid ion exchange membrane type electrolyte (proton exchange membrane). 

Lovley DR (2006) Microbial fuel cells Novel microbial physiologies and engineering approaches. Current Opinion in Biotechnology 17 327-332. 

Data obtained from Hyun Park, Doo and J. Gregory Zeikus. April, 2000. Electricity Generation in Microbial Fuel Cells Using Neutral Red as an Electronophore. Applied and Environmental Microbiology 66, No. 4 1292-1297. 

Patit P. Kundu is Professor in the Department of Polymer Science Technology at Calcutta University, India. He obtained his PhD in 1997 from IIT, Kharagpur, India. He has 67 research papers to his credit in international journals along with ten papers in national/international conferences, contributed 2 book chapters, and one patent. His research interest centers on the fields of synthesis and characterization of oil based rubber and nano-composites, microbial fuel cell, direct methanol fuel cell, microbial biodegradation of waste polyolefin fUm, tissue engineering and gene therapy. 

Logan BE,Regan JM. (2006). Microbial fuel cells—challenges and apphcations. Environmental Science Technology 40 5172-5180. 

Ringeisen BR, Ray R, Little B et al. (2007) A miniature microbial fuel cell operating with an aerobic anode chamber. J. Power Sources. 165 591—597. 

Biffinger JC, Ketron J, Ray R, Little B, Ringeisen BR (2007) A biofilm enhanced miniature microbial fuel cell using ShewaneUa oneidensis DSPIO and oxygen reduction cathodes. Biosens. Bioelectron. 22 1672-1679. 

From an application viewpoint. Some of best application of carbon nanofibers include ACNF as anodes in lithium-ion battery. Organic removal from waste water using, ACNF as cathode catalyst or as anodes for microbial fuel ceUs (MFCs), Electrochemical properties of ACNF as an electrode for supercapacitors. Adsorption of some toxic industrial solutions and air pollutants on ACNF [108-120]. 

Karra, U. et al.. Power generation and organics removal from wastewater using activated carbon nanofiber (ACNF) microbial fuel cells (MFCs). Int. J. Hydrogen Ener. 2012. 

As long as the oxidizing agent flows to the distal side of the membrane and an energy-rich substrate flows to the microbes, they can maintain the external electrical current. This is a form of microbial fuel cell. 

The unique combination of high mechanical stability, electrical conductivity, and surface area make carbon nanotubes (CNTs) a popular material for a wide range of biomedical applications, from microbial fuel cells to biochemical sensors [91-94]. Accordingly, CP composites have been investigated to synergize both mechanical and electrical properties of CNTs. 

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