Electron transfer by ion conductance in a soil bioelectric field. (February 2023)

• Record Type: Journal Article
• Authors: Han, Ting; Chen, Xiaodong; Wang, Kai; Emile Rushimisha, Iranzi; Yu, Xin; Yang, Side; Ye, Huike; Li, Yongtao; Li, Xiaojing
• Is Part Of: Sustainable energy technologies and assessments. Volume 55(2023)
• Publication Date: 2023-02
• Subjects: Soil microbial electrochemical system -- Bioelectric field -- Electron transfer -- Ion conductance -- Iron mineral; Renewable energy sources -- Periodicals; Energy development -- Technological innovations -- Periodicals; Electric power production -- Periodicals; Energy storage -- Periodicals; 333.79
• DOI: 10.1016/j.seta.2022.102902
• Languages: English
• ISSNs: 2213-1388

Abstract

Abstract: The efficacy of electron transfer determines the performance of soil microbial electrochemical systems (MESs). Ion conductance is an important endogenous route of electron transfer for the soil, yet its efficacy is unclear. Under the bioelectric field force generated in situ by indigenous soil microorganisms, dominant cations (Na + and Mg 2+ ) and anions (Cl − and SO4 2− ) were all transported to the cathode in soil MESs. Furthermore, the same valence state of ions exhibited different and even opposite effects on ion conductance according to the work done by the bioelectric field force over time, e.g., Na + and K + . Based on charges carried by migrated ions, we demonstrated that ion conductance was the main route of electron transfer in a soil MES, even for treatments with conductive magnetite and haematite. In contrast, electron shuttles contributed predominantly to electron transfer in ferrihydrite treatment. This was also supported by the characteristics of the charge transfer resistance and ohmic resistance according to the redundancy analysis with interpretation degrees of 93.96–94.25 %. Overall, this study provides profound insight into electron transfer by ion conductance in soil bioelectrochemical technology.