Boosting the Microbial Electrosynthesis of Formate by Shewanella Oneidensis MR-1 with an Ionic Liquid Cosolvent

Author

Ashwini Dantanarayana
Wassim El Housseini
Kevin Beaver
Monica Brachi
Timothy P. McFadden
Shelley D. Minteer, Missouri University of Science and TechnologyFollow

Abstract

Microbial electrosynthesis (MES) is a rapidly growing technology at the forefront of sustainable chemistry, leveraging the ability of microorganisms to catalyze electrochemical reactions to synthesize valuable compounds from renewable energy sources. The reduction of CO₂ is a major target application for MES, but research in this area has been stifled, especially with the use of direct electron transfer (DET)-based microbial systems. The major fundamental hurdle that needs to be overcome is the low efficiency of CO₂ reduction largely attributed to minimal microbial access to CO₂ owing to its low solubility in the electrolyte. With their tunable physical properties, ionic liquids present a potential solution to this challenge and have previously shown promise in facilitating efficient CO₂ electroreduction by increasing the CO₂ solubility. However, the use of ionic liquids in MES remains unexplored. In this study, we investigated the role of 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]) using Shewanella oneidensis MR-1 as a model DET strain. Electrochemical investigations demonstrated the ability of S. oneidensis MR-1 biocathodes to directly convert CO₂ to formate with a faradaic efficiency of 34.5 ± 26.1%. The addition of [EMIM][Ac] to the system significantly increased cathodic current density and enhanced the faradaic efficiency to 94.5 ± 4.3% while concurrently amplifying the product yield from 34 ± 23 μM to 366 ± 34 μM. These findings demonstrate that ionic liquids can serve as efficient, biocompatible cosolvents for microbial electrochemical reduction of CO₂ to value-added products, holding promise for more robust applications of MES.

Recommended Citation

A. Dantanarayana et al., "Boosting the Microbial Electrosynthesis of Formate by Shewanella Oneidensis MR-1 with an Ionic Liquid Cosolvent," ACS Applied Bio Materials, American Chemical Society, Jan 2024.

The definitive version is available at https://doi.org/10.1021/acsabm.4c01276

Department(s)

Chemistry

Keywords and Phrases

CO reduction 2; direct electron transfer; extracellular electron uptake; formate; ionic liquids; microbial electrosynthesis; solubility

International Standard Serial Number (ISSN)

2576-6422

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2024 American Chemical Society, All rights reserved.

Publication Date

01 Jan 2024