Improving mediated electron transport in anodic bioelectrocatalysis

Abstract

A novel design of a microbial fuel cell is realized by constructing bio-cocatalyst beads immobilized with riboflavin-secreting Escherichia coli and decoupling them from an anodic biocatalyst. A microbial fuel cell loaded with these bio-cocatalyst beads shows significantly enhanced performance without occupying an active electrode surface area.

A synthetic microbial consortium of Shewanella and Bacillus for enhanced generation of bioelectricity

“…The relatively low concentration of secreted flavins restricted the EET efficiency of MR-1. The synthetic microbial consortium was also found to be an effective way to improve the performance of MFCs by producing more electron shuttles or broadening carbon source (Tao et al, 2015;Venkataraman et al, 2011;Wang et al, 2014;Yang et al, 2015). The synthetic microbial consortium was also found to be an effective way to improve the performance of MFCs by producing more electron shuttles or broadening carbon source (Tao et al, 2015;Venkataraman et al, 2011;Wang et al, 2014;Yang et al, 2015).…”

“…It was an effective way to improve the EET efficiency of Shewanella by adding riboflavin to anolyte directly (Baron et al, 2009). The synthetic microbial consortium was also found to be an effective way to improve the performance of MFCs by producing more electron shuttles or broadening carbon source (Tao et al, 2015;Venkataraman et al, 2011;Wang et al, 2014;Yang et al, 2015).…”

Influence of Sludge Age on the Performance of a Cyclically Fed Microbial Fuel Cell Using Glycerol from Biodiesel

“…These microorganisms have the capacity of degrading organic matter and transferring the electrons produced in this process to the surface of an electrode. For this, two main mechanisms have been identified among the wide spectrum of electricity–generating microorganisms (EGM) , , : Direct electron transfer (DET), in which the bacteria directly adhere to the anodic surface and transfer the electrons through a cytochrome (directly adhered bacteria are exclusively active); or through the formation of conductive molecular pili (nanowires), which allow the electron transfer of more distant cells in the biofilm. DET is associated with the formation of an electroactive biofilm, whose thickness can reach 50–80 μm . Mediated electron transfer (MET), in which exogenous redox mediators are added to the anodic medium, or the microorganisms produce their own redox mediators, electron acceptors or even fermentation products which can be oxidized at the anode surface (H 2 , formate …).…”

Improving electron trans-inner membrane movements in microbial electrocatalysts

“…the electron conduit). 1,2 Some studies are centered on microbial metabolism, wherein the overexpression of glycerol dehydrogenase 3 or the manipulation of the cofactor 4 can enhance the electricity production while many more investigations are focused on the improvement of electron transport from the electron transport protein conduit to the extracellular electrode: exogenous electron shuttles (EESs) such as neutral red, 5 methyl viologen 6 and riboflavin 7,8 are usually used to accelerate electron transport between electricigens and the electrode; conjugated oligoelectrolytes (COEs) are added to assist the electron transport via the protein conduit and self-secreted flavins; [9][10][11] and the electrodes are modified with nanostructure materials such as nickel oxide nanoflaky arrays, 12,13 graphene/Au composites 14 and iron sulfide nanoparticles 15 to make better contact with OM-cytochromes of the microbial electrocatalysts and hence result in fast interfacial electrochemistry. However, the improved maximum output power densities reported from these studies range from ca.…”

“…S1). Dual-chamber MFCs with a microbial anode, a potassium ferricyanide cathode and a 2 kO resistor were utilized to allow anodic biofilm formation on the O 2 plasma-treated carbon cloth 8,37 as well as to test the performance of the whole-cell system. After a stable output of MFCs was achieved, the numbers of living wild-type MR-1 and NDH II recombinant strains at the carbon cloth were determined to be 15.89 AE 0.37 Â 10 6 colony forming units per square centimeter (CFU cm À2 ) and 15.98 AE 0.40 Â 10 6 CFU cm À2 , respectively.…”