Higher performances of open vs. closed circuit microbial fuel cell sensor for nitrate monitoring in water. Issue 3 (June 2022)

• Record Type: Journal Article
• Authors: Ren, Zhenxing; Ji, Guixia; Liu, Hongbo; Li, Ping; Huang, Jianhong; Lichtfouse, Eric
• Is Part Of: Journal of environmental chemical engineering. Volume 10:Issue 3(2022)
• Publication Date: 2022-06
• Subjects: Nitrate monitoring -- Open circuit -- Sensitivity and stability -- Response time -- Microbial community; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2022.107807
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: Microbial fuel cell (MFC) sensor exhibits attractive prospects for real-time monitoring of nitrate (NO3 - ) in water, with unique advantages of self-powering and simple structure; but its stability and sensitivity are unsatisfactory. In an attempt to address the limitations, here we employed an open-circuit MFC (O-MFC) sensor for real-time monitoring of NO3 - in water, compared to a conventional closed-circuit MFC (C-MFC) sensor. The stability of the O-MFC sensor was confirmed when subject to the continuous fluctuation of interfering substances including organic matter (acetate, 2–20 mM), SO4 2- (250–400 mg/L) and Fe 3+ (0.3–0.6 mg/L). For one-time and continuous monitoring of NO3 - at a concentration of 1–40 mg/L, the O-MFC sensor both achieved higher sensitivity than that of the C-MFC sensor; especially at a low NO3 - concentration of 1 mg/L, the changes of electrical signal (∆E) reached 10.0 ± 1.00 mV and 7.0 ± 0.85 mV respectively. In contrast, the C-MFC sensor failed to monitor at low NO3 - concentrations of 1 and 5 mg/L. Moreover, good linear correlation between ∆E and NO3 - concentration (R 2 = 0.907 and 0.981) was obtained from the O-MFC sensor. However, owing to the highly activity of EAB that mainly grows in the outer layer of biofilm, the response time of the O-MFC sensor is too long. Microbial community analysis further revealed that the open-circuit condition is more suitable for NO3 - monitoring in water, providing a new way to improve the performance of MFC sensors. Graphical Abstract: ga1 Highlights: A novel and cheap O-MFC sensor was constructed to determine nitrate in water. O-MFC sensor showed higher sensitivity and lower detection limits. O-MFC sensor is more resistant to organic shock and interfering ions. O-MFC sensor is more suitable for real time monitoring of nitrate in water.