Iron and Nickel Phthalocyanine‐Modified Nanocarbon Materials as Cathode Catalysts for Anion‐Exchange Membrane Fuel Cells and Zinc‐Air Batteries

Iron and nickel phthalocyanines along with different carbon supports, i. e., multi‐walled carbon nanotubes (MWCNT), graphene, carbide‐derived carbon, Vulcan carbon, and mesoporous carbon (MC, from Pajarito Powder, LLC), are used to prepare six bimetallic (Fe, Ni) N‐doped carbon‐based catalysts. The aim of this work is to investigate the electrocatalytic activity of bimetal phthalocyanine‐modified nanocarbon catalysts, e. g., the effect of carbon supports on the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), including the anion‐exchange membrane fuel cell (AEMFC) and rechargeable zinc‐air battery (RZAB) configuration. The catalysts exhibit excellent electrocatalytic activity as exemplified by their half‐wave potential (E1/2) for ORR and the potential at which the OER current density reaches 10 mA cm−2 (Ej=10), but the best performing catalysts are FeNiN−MC (E1/2=0.88 V, Ej=10=1.58 V) and FeNiN−MWCNT (E1/2=0.87 V, Ej=10=1.59 V). In AEMFC analyses, FeNiN−MWCNT cathode provides peak power density (Pmax) of 406 mW cm−2, slightly higher than that of FeNiN−MC (Pmax=386 mW cm−2). Both catalysts exhibit a good RZAB performance (Pmax of 85 mW cm−2 for FeNiN−MWCNT). The assembled RZABs run stably for 48 h without any significant loss of performance. Effect of carbon support: Bimettalic iron and nickel phthalocyanine doped nanocarbon supports were studied for potential AEMFC and ZAB cathode catalyst. FeNiN−MWCNT and FeNiN−MC catalysts exhbhited highest ORR and OER activity (E1/2=0.87 and 0.88 V; Ej=10=1.59 and 1.58 V, respectively). FeNiN−MWCNT outperforms the state‐of‐the‐art Pt/C catalyst in both AEMFC and RZAB tests.