Fe3C-modified porous carbon as anode electrocatalyst for improving extracellular electron transfer and removing Cr(VI) in microbial fuel cells

Abstract

The anode, as a host site for electricigens, is regarded as an important determinant of the power generation of microbial fuel cells (MFCs), which is confined by the sluggish extracellular electron transfer (EET) at the electricigens/anode interface. In this study, a novel spindle-shaped material, Fe-modified porous carbon (Fe3C/PC), was rationally designed to boost the efficiency of EET. As expected, the MFCs equipped with the as-synthesized Fe3C/PC@CF anode exhibited excellent electrocatalytic activity for charge transfer and achieved much higher power density (1425 mW m−2). Ultimately, mature MFCs would be used to treat real effluent and Cr(VI) sewage. The excellent performance of MFCs was due to the active surface area provided by the porous carbon in Fe3C/PC@CF, which was conducive to electricigens adhesion, and the Fe3C doping provided abundant catalytic active sites for the anode. This work provides a new concept for the design of high performance anode electrocatalysts for MFCs and wastewater treatment.