Photosynthetic microbial fuel cells for methanol treatment using graphene electrodes

Kalimuthu Jawaharraj; Pawan Sigdel; Zhengrong Gu; Govarthanan Muthusamy; Rajesh Kumar Sani; Venkataramana Gadhamshetty

doi:10.1016/j.envres.2022.114045

Photosynthetic microbial fuel cells for methanol treatment using graphene electrodes

Environ Res. 2022 Dec;215(Pt 1):114045. doi: 10.1016/j.envres.2022.114045. Epub 2022 Aug 20.

Authors

Kalimuthu Jawaharraj¹, Pawan Sigdel², Zhengrong Gu³, Govarthanan Muthusamy⁴, Rajesh Kumar Sani⁵, Venkataramana Gadhamshetty⁶

Affiliations

¹ Civil and Environmental Engineering, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA; BuG ReMeDEE Consortia, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA; 2D-materials for Biofilm Engineering, Science and Technology (2DBEST) Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA; Data-Driven Materials Discovery for Bioengineering Innovation Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA.
² Civil and Environmental Engineering, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA; 2D-materials for Biofilm Engineering, Science and Technology (2DBEST) Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA.
³ Agricultural and Biosystems Engineering, South Dakota State University, 2100 University Station, Brookings, SD, 57701, USA; 2D-materials for Biofilm Engineering, Science and Technology (2DBEST) Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA.
⁴ Department of Environmental Engineering, Kyungpook National University, Daegu, South Korea, 80 Daehak-ro, Buk-gu, Daegu, South Korea; Department of Biomaterials, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Chennai, 600 077, Tamil Nadu, India.
⁵ Chemical and Biological Engineering, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA; BuG ReMeDEE Consortia, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA; 2D-materials for Biofilm Engineering, Science and Technology (2DBEST) Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA; Data-Driven Materials Discovery for Bioengineering Innovation Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA.
⁶ Civil and Environmental Engineering, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA; BuG ReMeDEE Consortia, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA; 2D-materials for Biofilm Engineering, Science and Technology (2DBEST) Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA; Data-Driven Materials Discovery for Bioengineering Innovation Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD, 57701, USA. Electronic address: Venkata.Gadhamshetty@sdsmt.edu.

PMID: 35995227
DOI: 10.1016/j.envres.2022.114045

Abstract

Photosynthetic microbial fuel cells (pMFC) represent a promising approach for treating methanol (CH₃OH) wastewater. However, their use is constrained by a lack of knowledge on the extracellular electron transfer capabilities of photosynthetic methylotrophs, especially when coupled with metal electrodes. This study assessed the CH₃OH oxidation capabilities of Rhodobacter sphaeroides 2.4.1 in two-compartment pMFCs. A 3D nickel (Ni) foam modified with plasma-grown graphene (Gr) was used as an anode, nitrate mineral salts media (NMS) supplemented with 0.1% CH₃OH as anolyte, carbon brush as cathode, and 50 mM ferricyanide as catholyte. Two simultaneous pMFCs that used bare Ni foam and carbon felt served as controls. The Ni/Gr electrode registered a two-fold lower charge transfer resistance (0.005 kΩ cm²) and correspondingly 16-fold higher power density (141 mW/m²) compared to controls. The underlying reasons for the enhanced performance of R. sphaeroides at the graphene interface were discerned. The real-time polymerase chain reaction (PCR) analysis revealed the upregulation of cytochrome c oxidase, aa3 type, subunit I gene, and Flp pilus assembly protein genes in the sessile cells compared to their planktonic counterparts. The key EET pathways used for sustaining CH₃OH oxidation were discussed.

Keywords: Graphene; Methanol; Microbial fuel cells; Photosynthetic; Rhodobacter.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Bioelectric Energy Sources*
Carbon
Carbon Fiber
Electrodes
Electron Transport Complex IV
Ferricyanides
Graphite*
Methanol
Nickel
Nitrates
Salts
Wastewater

Substances

Carbon Fiber
Ferricyanides
Nitrates
Salts
Waste Water
Carbon
Graphite
Nickel
Electron Transport Complex IV
Methanol