Creation of Conductive Graphene Materials by Bacterial Reduction Using Shewanella Oneidensis

Abstract

Graphene's maximized surface‐to‐volume ratio, high conductance, mechanical strength, and flexibility make it a promising nanomaterial. However, large‐scale graphene production is typically cost‐intensive. This manuscript describes a microbial reduction approach for producing graphene that utilizes the bacterium Shewanella oneidensis in combination with modern nanotechnology to enable a low‐cost, large‐scale production method. The bacterial reduction approach presented in this paper increases the conductance of single graphene oxide flakes as well as bulk graphene oxide sheets by 2.1 to 2.7 orders of magnitude respectively while simultaneously retaining a high surface‐area‐to‐thickness ratio. Shewanella ‐mediated reduction was employed in conjunction with electron‐beam lithography to reduce one surface of individual graphene oxide flakes. This methodology yielded conducting flakes with differing functionalization on the top and bottom faces. Therefore, microbial reduction of graphene oxide enables the development and up‐scaling of new types of graphene‐based materials and devices with a variety of applications including nano‐composites, conductive inks, and biosensors, while avoiding usage of hazardous, environmentally‐unfriendly chemicals.

Organic Microbial Electrochemical Transistor Monitoring Extracellular Electron Transfer

“…In this process, typically metal oxides or even polarized electrodes take the role of terminal-end electron acceptors instead of oxygen. EET is important for a wide variety of industrial applications including energy generation via microbial fuel cells (MFCs), [1] biobatteries, [2] and whole cell-based biophotovoltaic cells (BPVCs), [3] storing electrical energy in chemical bonds (microbial electrosynthesis), [4] detection of analytes, [5,6] or even cost-efficient preparation of graphene from graphene oxide [7] in microbial electrochemical systems (MESs). [8] From the perspective of human health, EET has recently been implicated in colonization of the human gut by pathogenic bacteria.…”

Graphene: An Antibacterial Agent or a Promoter of Bacterial Proliferation?

“…The bacterial reduction of GO is a promising method that can be integrated into the fabrication of GMs for diverse applications. Its lower cost and non-toxicity represent clear advantages over chemical routes of GO reduction ( Raveendran et al., 2013 ; Lehner et al., 2019 ).…”

Graphene: A new technology for agriculture

“…There is also the possibility of producing graphene from crop residues, which could further reduce production costs, e.g., agricultural waste from sugarcane bagasse (Somanathan et al, 2015). In addition, graphene can be produced from bacteria such as Shewanella (Lehner et al, 2019), with high efficiency in terms of cost, time savings and the environment in comparison to chemical methods of graphene production.…”