Improved performance of microbial fuel cells through addition of trehalose lipids

AbstractElectron transfer from microorganisms to the electrode is the key process in microbial fuel cells (MFCs). In this study, a trehalose lipid was added to a Rhodococcus pyridinivorans-inoculated MFC to improve the power output by enhancing electron transfer. Upon trehalose lipid addition, the current density and maximum power density were increased by 1.83 times and 5.93 times, respectively. Cyclic voltammetry analysis revealed that the addition of trehalose lipid increased the electron transfer performance, while electrochemical impedance spectroscopy results proved a decrease in internal resistance. Microscopy images showed that the trehalose lipid-treated bacteria interacted more closely with various fagellum-like contacts, while in the pure trehalose lipid (200 mg/L), pores were obviously observed in the cell surface.ImportanceImproving the power output of microbial fuel cells by the addition of bio-surfactants have been proved to be a novel method. However, only rhamnolipid and sophorolipid are certified to be effective. Trehalose lipid is a common material in cosmetic and bio-medicine industry. Our research broaden the application of bio-surfactant in MFC and preliminarily explain the mechanism.HighlightsTrehalose lipid enhanced MFC power generationTrehalose lipid decrease MFC internal resistancePores were observed with the addition of trehalose lipidAddition of bio-surfactant is a promising way to increase MFC performance