Electrogenic Biofilm Development Determines Charge Accumulation and Resistance to pH Perturbation

The electrogenic biofilm and the bio-electrode interface are the key biocatalytic components in bioelectrochemical systems (BES) and can have a large impact on cell performance. This study used four different anodic carbons to investigate electrogenic biofilm development to determine the influence o...

Full description

Bibliographic Details
Main Authors: Iain S. Michie, Richard M. Dinsdale, Alan J. Guwy, Giuliano C. Premier
Format: Article
Language:English
Published: MDPI AG 2020-07-01
Series:Energies
Subjects:
Online Access:https://www.mdpi.com/1996-1073/13/14/3521
_version_ 1797562909312679936
author Iain S. Michie
Richard M. Dinsdale
Alan J. Guwy
Giuliano C. Premier
author_facet Iain S. Michie
Richard M. Dinsdale
Alan J. Guwy
Giuliano C. Premier
author_sort Iain S. Michie
collection DOAJ
description The electrogenic biofilm and the bio-electrode interface are the key biocatalytic components in bioelectrochemical systems (BES) and can have a large impact on cell performance. This study used four different anodic carbons to investigate electrogenic biofilm development to determine the influence of charge accumulation and biofilm growth on system performance and how biofilm structure may mitigate against pH perturbations. Power production was highest (1.40 W/m<sup>3</sup>) using carbon felt, but significant power was also produced when felt carbon was open-circuit acclimated in a control reactor (0.95 W/m<sup>3</sup>). The influence of carbon material on electrogenic biofilm development was determined by measuring the level of biofilm growth, using sequencing to identify the microbial populations and confocal microscopy to understand the spatial locations of key microbial groups. <i>Geobacter</i> spp. were found to be enriched in closed-circuit operation and these were in close association with the carbon anode, but these were not observed in the open-circuit controls. Electrochemical analysis also demonstrated that the highest mid-point anode potentials were close to values reported for cytochromes from <i>Geobacter sulfurreductans</i>. Biofilm development was greatest in felt anodes (closed-circuit acclimated 1209 ng/μL DNA), and this facilitated the highest pseudo-capacitive values due to the presence of redox-active species, and this was associated with higher levels of power production and also served to mitigate against the effects of low-pH operation. Supporting carbon anode structures are key to electrogenic biofilm development and associated system performance and are also capable of protecting electrochemically active bacteria from the effects of environmental perturbations.
first_indexed 2024-03-10T18:35:18Z
format Article
id doaj.art-208deebca544474798dd59e4bafef6aa
institution Directory Open Access Journal
issn 1996-1073
language English
last_indexed 2024-03-10T18:35:18Z
publishDate 2020-07-01
publisher MDPI AG
record_format Article
series Energies
spelling doaj.art-208deebca544474798dd59e4bafef6aa2023-11-20T06:14:20ZengMDPI AGEnergies1996-10732020-07-011314352110.3390/en13143521Electrogenic Biofilm Development Determines Charge Accumulation and Resistance to pH PerturbationIain S. Michie0Richard M. Dinsdale1Alan J. Guwy2Giuliano C. Premier3Sustainable Environment Research Centre (SERC), Faculty of Computing, Engineering and Science, University of South Wales, Pontypridd, Mid-Glamorgan CF37 1DL, UKSustainable Environment Research Centre (SERC), Faculty of Computing, Engineering and Science, University of South Wales, Pontypridd, Mid-Glamorgan CF37 1DL, UKSustainable Environment Research Centre (SERC), Faculty of Computing, Engineering and Science, University of South Wales, Pontypridd, Mid-Glamorgan CF37 1DL, UKSustainable Environment Research Centre (SERC), Faculty of Computing, Engineering and Science, University of South Wales, Pontypridd, Mid-Glamorgan CF37 1DL, UKThe electrogenic biofilm and the bio-electrode interface are the key biocatalytic components in bioelectrochemical systems (BES) and can have a large impact on cell performance. This study used four different anodic carbons to investigate electrogenic biofilm development to determine the influence of charge accumulation and biofilm growth on system performance and how biofilm structure may mitigate against pH perturbations. Power production was highest (1.40 W/m<sup>3</sup>) using carbon felt, but significant power was also produced when felt carbon was open-circuit acclimated in a control reactor (0.95 W/m<sup>3</sup>). The influence of carbon material on electrogenic biofilm development was determined by measuring the level of biofilm growth, using sequencing to identify the microbial populations and confocal microscopy to understand the spatial locations of key microbial groups. <i>Geobacter</i> spp. were found to be enriched in closed-circuit operation and these were in close association with the carbon anode, but these were not observed in the open-circuit controls. Electrochemical analysis also demonstrated that the highest mid-point anode potentials were close to values reported for cytochromes from <i>Geobacter sulfurreductans</i>. Biofilm development was greatest in felt anodes (closed-circuit acclimated 1209 ng/μL DNA), and this facilitated the highest pseudo-capacitive values due to the presence of redox-active species, and this was associated with higher levels of power production and also served to mitigate against the effects of low-pH operation. Supporting carbon anode structures are key to electrogenic biofilm development and associated system performance and are also capable of protecting electrochemically active bacteria from the effects of environmental perturbations.https://www.mdpi.com/1996-1073/13/14/3521biofilmcarbon materialcharge accumulationmicrobial fuel cellspH
spellingShingle Iain S. Michie
Richard M. Dinsdale
Alan J. Guwy
Giuliano C. Premier
Electrogenic Biofilm Development Determines Charge Accumulation and Resistance to pH Perturbation
Energies
biofilm
carbon material
charge accumulation
microbial fuel cells
pH
title Electrogenic Biofilm Development Determines Charge Accumulation and Resistance to pH Perturbation
title_full Electrogenic Biofilm Development Determines Charge Accumulation and Resistance to pH Perturbation
title_fullStr Electrogenic Biofilm Development Determines Charge Accumulation and Resistance to pH Perturbation
title_full_unstemmed Electrogenic Biofilm Development Determines Charge Accumulation and Resistance to pH Perturbation
title_short Electrogenic Biofilm Development Determines Charge Accumulation and Resistance to pH Perturbation
title_sort electrogenic biofilm development determines charge accumulation and resistance to ph perturbation
topic biofilm
carbon material
charge accumulation
microbial fuel cells
pH
url https://www.mdpi.com/1996-1073/13/14/3521
work_keys_str_mv AT iainsmichie electrogenicbiofilmdevelopmentdetermineschargeaccumulationandresistancetophperturbation
AT richardmdinsdale electrogenicbiofilmdevelopmentdetermineschargeaccumulationandresistancetophperturbation
AT alanjguwy electrogenicbiofilmdevelopmentdetermineschargeaccumulationandresistancetophperturbation
AT giulianocpremier electrogenicbiofilmdevelopmentdetermineschargeaccumulationandresistancetophperturbation