Design of Iron(II) Phthalocyanine‐Derived Oxygen Reduction Electrocatalysts for High‐Power‐Density Microbial Fuel Cells

Iron(II) phthalocyanine (FePc) deposited onto two different carbonaceous supports was synthesized through an unconventional pyrolysis‐free method. The obtained materials were studied in the oxygen reduction reaction (ORR) in neutral media through incorporation in an air‐breathing cathode structure and tested in an operating microbial fuel cell (MFC) configuration. Rotating ring disk electrode (RRDE) analysis revealed high performances of the Fe‐based catalysts compared with that of activated carbon (AC). The FePc supported on Black‐Pearl carbon black [Fe‐BP(N)] exhibits the highest performance in terms of its more positive onset potential, positive shift of the half‐wave potential, and higher limiting current as well as the highest power density in the operating MFC of (243±7) μW cm(−2), which was 33 % higher than that of FePc supported on nitrogen‐doped carbon nanotubes (Fe‐CNT(N); 182±5 μW cm(−2)). The power density generated by Fe‐BP(N) was 92 % higher than that of the MFC utilizing AC; therefore, the utilization of platinum group metal‐free catalysts can boost the performances of MFCs significantly.