Enhanced MFC sensor performances and extracellular electron transport efficiency mediated by biochar and underlying biochemical mechanisms. (15th April 2023)

• Record Type: Journal Article
• Authors: Zhang, Ke; Cao, Huiling; Luo, Hongbing; Chen, Wei; Chen, Jia
• Is Part Of: Journal of environmental management. Volume 332(2023)
• Publication Date: 2023-04-15
• Subjects: Biochar -- MFC sensor Performance -- Extracellular electron transport -- Microbiological mechaism; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2023.117282
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: To explore the application of biosensor in real-time monitoring of composite heavy metal polluted wastewater in view of the low performance of MFC sensor, this study used sodium alginate to immobilize biochar to the anode of MFC biosensor, and conducted a study on the sensor performance and related biological processes. The results showed that under the optimal HRT conditions, the output power of the MFC-sensor (BC-300) was 0.432 W/m 3 after biochar modification, which was much higher than the highest power density of CG and BC-0 of 0.117 and 0.088 W/m 3 . The correlation coefficient was greater than that of the control group at the plating wastewater concentration of 0.1–1.0 M and had a wider detection range, and the time to recover the output voltage was 1/3 of that of the control group. The biochar significantly promoted the sensitivity, interference resistance, recovery and anti-interference performance of the MFC-sensor. The intrinsic mechanism was that the composition and structure of biochar lead to a 1.53 fold increase in the abundance of electrogenic microorganisms and the abundance of functional genes such as cytochrome c (MtrABC, CymA, Cox, etc.) and flavin (riba, Rib B, gdh, ushA, IDH, etc.) increased by about 1.03–3.20 times, which promoted the shift of electrons from intracellular to extracellular receptors and significantly improved the electron transfer and the energy metabolism efficiency. The results of this study can provide a reference for the application of MFCsensor to the detection of complex heavy metal effluents. Graphical abstract: Image 1 Highlights: Biochar enhanced the correlation, sensitivity and resilience of the MFC sensor. Microbiological mechanism of biochar enhanced sensor performance was revealed. The relationship between energy metabolism and biochar in MFC sensor was elucidated. Electron transfer efficiency and gene abundance affected the performance of sensor.