Microbial fuel cell using ferrous ion activated persulfate as a cathodic reactant

In the present paper, the K2S2O8–Fe2+ system without pH adjustment was used as a cathodic reactant in a two-chamber microbial fuel cell (MFC) for the first time. The performance of the MFC with K2S2O8–Fe2+ system was discussed and compared with that of K2S2O8 and H2O2–Fe2+ system, respectively. These results demonstrated that the introduced ferrous ion could improve the power generation significantly. The initial K2S2O8/Fe2+ molar ratios and the pH, which can affect the performance of MFC, were discussed later. The results revealed that K2S2O8–Fe2+ system achieved the best performance at K2S2O8/Fe2+ molar ratios of 2:1 and the K2S2O8-Fe2+ system was stable with varying pH value. This study demonstrated that the K2S2O8–Fe2+ system can be used as an effective cathodic reactant due to its excellent performance.

► The authors proposed a novel cathodic reagent of K2S2O8–Fe2+ system in a two-chamber MFC.
► The power generation of the MFC with K2S2O8–Fe2+ was higher than that with K2S2O8.
► The K2S2O8–Fe2+ system performed better than H2O2–Fe2+ system in MFC.
► The voltage output of MFC using K2S2O8–Fe2+ system was just slightly influenced by pH.