Higher performances of open vs. closed circuit microbial fuel cell sensor for nitrate monitoring in water

Microbial fuel cell (MFC) sensor exhibits attractive prospects for real-time monitoring of nitrate (NO3-) in water, with unique advantages self-powering and simple structure; but its stability sensitivity are unsatisfactory. In an attempt to address the limitations, here we employed open-circuit MFC (O-MFC) NO3- compared a conventional closed-circuit (C-MFC) sensor. The O-MFC was confirmed when subject continuous fluctuation interfering substances including organic matter (acetate, 2–20 mM), SO42- (250–400 mg/L) Fe3+ (0.3–0.6 mg/L). For one-time at concentration 1–40 mg/L, both achieved higher than that C-MFC sensor; especially low 1 changes electrical signal (∆E) reached 10.0 ± 1.00 mV 7.0 0.85 respectively. contrast, failed monitor concentrations 5 mg/L. Moreover, good linear correlation between ∆E (R2 = 0.907 0.981) obtained from However, owing highly activity EAB mainly grows outer layer biofilm, response time is too long. community analysis further revealed condition more suitable providing new way improve performance sensors.