An Efficient Bio‐inspired Oxygen Reduction Reaction Catalyst: MnOx Nanosheets Incorporated Iron Phthalocyanine Functionalized Graphene. Issue 3 (27th November 2020) - Wu, Xing
Abstract : Oxygen reduction reaction (ORR) catalysts play a critical role in energy storage and conversion devices and have been attracted enormous interests, and however, it remains challenging to develop highly active cheap catalysts in a simple and green route. Inspired by the heme‐copper oxidases (HOCs), in which the ORR active center is originated from the incorporation of Fe‐N4 with copper atom, we here developed a fine manganese oxide nanosheets (MnO x NSs) integrated with iron phthalocyanine (FePc) anchored on highly conductive graphene (MnO x /FePc‐G) through a green route only involve ethanol as the reagent. The bio‐inspired catalyst MnO x /FePc‐G demonstrated high ORR activity with a half‐wave potential ( E 1/2 ) of 0.887 V, about 57 mV more positive than that of Pt/C. And the current density ( j ) at 0.9 V is about 1.9 mA cm −2, which is three times of Pt/C and FePc‐G. More importantly, the bio‐inspired systems show superior stability in comparison to commercial Pt/C, showing a potential of 0.863 V to deliver a j of 3 mA cm −2 after 18 000 s polarization, about 80 mV higher than that of 0.783 V for Pt/C. The high activity is contributed by the integration of the FePc and MnO x NSs that plays the role to assist the cleavage of the O2 bond. Our approach provides a new evidence to develop highly efficient ORR catalysts through imitate the naturally involved systems through a simple route. Abstract : Inspired by the heme‐copper oxidases, fine manganese oxide nanosheets integrated with iron phthalocyanine anchored on highly conductive graphene have been prepared, and the bio‐inspired composite show significant enhanced ORR activity due to the synergistic effect of the iron phthalocyanine and the ultrafine manganese oxide nanosheets.