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 (E-1/2) for ORR and the potential at which the OER current density reaches 10 mA cm(-2) (E-j=10), but the best performing catalysts are FeNiN-MC (E-1/2=0.88 V, E-j=10=1.58 V) and FeNiN-MWCNT (E-1/2=0.87 V, E-j=10=1.59 V). In AEMFC analyses, FeNiN-MWCNT cathode provides peak power density (P-max) of 406 mW cm(-2), slightly higher than that of FeNiN-MC (P-max=386 mW cm(-2)). Both catalysts exhibit a good RZAB performance (P-max of 85 mW cm(-2) for FeNiN-MWCNT). The assembled RZABs run stably for 48 h without any significant loss of performance.