Overestimation of biofilm conductance determined by using the split electrode as the microbial respiration

JOURNAL OF POWER SOURCES

卷:453

Article

Liu, Panpan¹  Liang, Peng¹  Beyenal, Haluk²  Huang, Xia¹ 

[1] Tsinghua Univ, State Key Joint Lab Environm Simulat & Pollut Con, Sch Environm, Beijing 100084, Peoples R China

[2] Washington State Univ, Gene & Voiland Sch Chem Engn & Bioengn, Pullman, WA 99163 USA

关键词: Biofilm conductance;    Extracellular electron transfer;    Geobacter sulfurreducens;    Bioelectronics;    Microbial electrochemistry;   

DOI  :  10.1016/j.jpowsour.2020.227906

来源: Elsevier

【 摘 要 】

Advancing the application of bioelectrochemical systems necessitates the comprehensive understanding of electron transfer process in electrode-associated biofilm. While in situ electrical measurement by using the split electrode can illustrate the electron conduction in biofilm, the accuracy and interpretation of the obtained data is still in debate. Here, conductance of Geobacter sulfurreducens biofilm is measured by using the split electrode as substrate concentration is changed. Biofilm conductance decreases with the current production as the consumption of substrate. In addition, the measured conductance increases with the area of drain electrode (13.8 +/- 1.8 mu S for 0.5 cm(2) and 29.4 +/- 4.2 mu S for 1 cm(2)). These results suggest the measured conductance of biofilm is influenced by microbial metabolism. This effect will diminish when the measurement is performed by using electrochemical impedance spectroscopy or under non-turnover condition. Our results provide the insight on the electrochemical origin of biofilm conductance determined by the in situ electrical measurement.

【 授权许可】

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