Enhanced electricity production in single-chamber MFCs with air cathodes decorated by Fe–N–C catalysts derived from 5H-dibenz [b,f] azepine-5-carboxamide (Carbamazepine)

Abstract

For practical applications of microbial fuel cells (MFCs), 5H-dibenz [b,f] azepine-5-carboxamide (Carbamazepine, CBZ) was used as the organic precursor for the synthesis of catalysts composed of Fe–N–C complexes (named as Fe-CBZ-Cats) through a sacrificial support method. Characterizations by SEM, XPS and TEM-EDS elemental mapping show that the synthesized Fe-CBZ-Cats have porous structure and uniformly dispersed Fe/N/C complex centers which could play key roles in effective ORR. Linear scanning voltammetry (LSV) measurements show that the synthesized Fe-CBZ-Cats exhibits ORR activity comparable to commercial Pt/C catalysts under the same catalyst loading (2 mg cm−2). The maximum power density produced by cathode-limiting MFCs with Fe-CBZ-Cats air cathodes was 431 ± 23 μW cm−2, higher than those in the control MFCs with Pt/C air cathodes (403 ± 13 μW cm−2) and activated carbon air cathodes (296 ± 24 μW cm−2). In addition, the toxicity tolerance of the synthesized Fe-CBZ-Cats is much higher than Pt/C.