Highly Active Bidirectional Electron Transfer by a Self‐Assembled Electroactive Reduced‐Graphene‐Oxide‐Hybridized Biofilm

Abstract

Low extracellular electron transfer performance is often a bottleneck in developing high-performance bioelectrochemical systems. Herein, we show that the self-assembly of graphene oxide and Shewanella oneidensis MR-1 formed an electroactive, reduced-graphene-oxide-hybridized, three-dimensional macroporous biofilm, which enabled highly efficient bidirectional electron transfers between Shewanella and electrodes owing to high biomass incorporation and enhanced direct contact-based extracellular electron transfer. This 3D electroactive biofilm delivered a 25-fold increase in the outward current (oxidation current, electron flux from bacteria to electrodes) and 74-fold increase in the inward current (reduction current, electron flux from electrodes to bacteria) over that of the naturally occurring biofilms.

Wettability‐Regulated Extracellular Electron Transfer from the Living Organism of Shewanella loihica PV‐4

“…[2,3] For the model organisms of the genus Shewanella, multiheme c-type cytochromes located on the outer membrane (OMCs) are the main redox-active species that mediate electron flow from the cell interior to the external insoluble electron acceptors across the insulated phospholipid bilayer cellular envelope.…”

Bioinspired Nanosucker Array for Enhancing Bioelectricity Generation in Microbial Fuel Cells

“…This work not only illustrates a novel route to enhance the extracellular electron transfer and bioelectricity generation for MFCs, but also provides a useful platform to understand and rationally design functional living microorganisms/electrode interface for other kinds of bioelectrochemical systems and devices, such as microbial electrolysis cells, microbial reverse-electrodialysis cells, microbial electrosynthesis. [51][52][53][54] The proposed sucking effect can also be combined with the existing anode modifi cation strategies, and future work from our group will focus on incorporating the sucker arrays inside 3D porous structured anodes to further improve the electron transfer process.…”

Electrifying microbes for the production of chemicals

“…A S. oneidensis biofilm assembled with embodied graphene oxide could uptake electrons 74 times more efficiently (Yong et al, 2014). Oligoelectrolytes can also facilitate electron transfer from the cathode by inserting itself in the lipid membrane of bacteria to enable transmembrane charge transfer as demonstrated by Thomas et al (2013).…”