Hybrid binuclear-cobalt-phthalocyanine as oxygen reduction reaction catalyst in single chamber microbial fuel cells.

A novel hybrid binuclear-cobalt-phthalocyanine (Bi-CoPc) is developed as the cathode catalyst to replace the costly platinum (Pt) in single chamber microbial fuel cells (SCMFCs). Bi-CoPc/C is integrated with metal oxides (NiO and CoO) to form macrocyclic complex for enhanced oxygen reduction rate (ORR). The characteristics of hybrid catalysts (Bi-CoPc/C–CoO and Bi-CoPc/C–NiO) are compared with Co-contained catalysts (CoPc/C and Bi-CoPc/C) and metal oxide catalysts (NiO and CoO). The increase in O and N functional groups indicates the benefits of NiO and CoO to the cathode catalysts. The cyclic voltammetry (CV) shows the reduction peak for Bi-CoPc/C–NiO and Bi-CoPc/C–CoO at −0.12 V and −0.22 V, respectively. The power densities (368 mW m −2 and 400 mW m −2 ) of SCMFCs with Bi-CoPc/C–CoO and Bi-CoPc-NiO/C are the highest among the cathodes tested, and close to that of Pt (450 mW m −2 ). This study demonstrates that hybrid Bi-CoPc/C with metal oxides has a great potential as a cost-effective catalyst in MFCs. [ABSTRACT FROM AUTHOR]