Nano-Fe3C@2D-NC@CC as anode for improving extracellular electron transfer and electricity generation of microbial fuel cells

Abstract

Microbial fuel cells (MFCs) are attractive because they can harvest energy from sewage, but challenge remains in achieving valuable power density. To address this issue, we develop a novel binder-free anode, Nano-Fe3C@2D-NC@CC, by assembling 2D Zn-Fe-MOF arrays on the fibers of carbon cloth and subsequently carbonizing MOF. This fabrication results in a unique configuration that nano-Fe3C particles are highly dispersed on N-doped carbon arrays vertically standing on carbon fibers. The standing 2D arrays not only benefit bacterial adhesion but also guarantee nano-Fe3C particles with abundant sites for the charge transfer between bacteria and anode. Consequently, a superior power density (1606 ± 52 mW m − 2) is harvested when the resultant Nano-Fe3C@2D-NC@CC is evaluated as the anode in MFCs based on a mixed bacterium culture. The facile fabrication of Nano-Fe3C@2D-NC@CC paves a promising path for the application of MFCs in large scale.