Graphene oxide electrodeposited electrode enhances start-up and selective enrichment of exoelectrogens in bioelectrochemical systems

Abstract

This study seeks to assess the impact that the anodic electrodeposition of graphene oxide (GO) has on the start-up process and on the development of microbial communities on the anode of BESs. The GO electrodeposited electrodes were characterised in abiotic conditions to verify the extent of the modification and were then transferred to a bioelectrochemical reactor. Results showed that the modified electrode allowed for a reduced start-up time compared to the control electrode. After three months, high throughput sequencing was performed, revealing that electrochemically reduced graphene oxide acts as a selective agent toward exoelectrogenic bacteria as Geobacter. Overall, this study shows that GO modified electrodes enhance biofilm build up in BES.

Water Electrolysis Carried Out on Microelectrodes to Obtain New Insights into the Regulation of Cytosolic pH

“…These modifications facilitated obtaining larger currents during electroreduction of water. The reduced graphene oxide was electrodeposited onto the microelectrodes by adapting a procedure previously reported in the literature . Briefly, the reduced graphene oxide was deposited onto the microelectrodes by cycling the potential of the microelectrodes in between +0.85 V and −0.95 V vs .…”

Nanocomposite Materials Based on Electrochemically Synthesized Graphene Polymers: Molecular Architecture Strategies for Sensor Applications

“…The values for this parameter vary widely between different studies, depending on the chemical constitution of the chosen electrode and the pH values of the medium, but most studies report the application of a potential of approximately −1.0 V (vs. SCE) [56]. The intense cathodic potential aims to promote the reduction of the oxygenated groups of the graphene oxide sheets, making their deposition on the electrode possible [61,[63][64][65][66]. When reduced or partially reduced (depending on the conditions, the electrodeposited graphene oxide will be partially reduced), the sheets become more insoluble and stick to the surface of the conductive material [56,61,64,65].…”

Comparison of Activation Methods for 3D-Printed Electrodes for Microbial Electrochemical Technologies

“…The aim of the abiotic characterization was to assess the impact of the different activation procedures on the electrochemical performance of the electrodes. Although the use of the Fe(CN) 6 ] 4−/3− pair to evaluate the electrodes activity is not directly transferable to other electrochemical systems (e.g., bioelectrochemical systems), it provides an preliminary estimate of the effectiveness of the electrode [2,15,16]. The results from the CV tests (Figure 2) revealed a poor electrochemical performance of the electrochemically activated electrode compared to the DMF-and acetone-activated electrodes.…”

“…The advance of a multidisciplinary field like bioelectrochemistry runs parallel to that of other fields of knowledge, such as microbiology, electrochemistry, materials science or manufacturing engineering, in an interdependent manner [1]. Thus, the appearance of new materials, frequently referred to as nanomaterials, has opened new perspectives in the development of microbial electrochemical technologies (MET), which could contribute to overcoming global challenges in sustainable energy and waste management, as numerous publications have already shown [2][3][4][5]. Another technological breakthrough capable of evolving METs is additive manufacturing (AM)-commonly known as 3D printing-which has led to a paradigm shift in manufacturing engineering and has revealed potential in the development of functional MET prototypes [6].…”