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

Abstract

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.

Recent Advances in Non‐Precious Metal Single‐Atom Electrocatalysts for Oxygen Reduction Reaction in Low‐Temperature Polymer‐Electrolyte Fuel Cells

“…One of the first approaches in the preparation of carbonbased catalysts with M-N x sites has been the functionalisation of pre-existing carbon materials using high-temperature pyrolysis in the presence of precursors of transition metal and nitrogen. Various nanocarbon materials, such as carbon black, [13,52,53] carbon nanotubes (CNTs), [54] carbide-derived carbon, [55] graphene, [56] mesoporous carbons [57] and composites of these [58][59][60] have been used as substrates. For doping, a great variety of nitrogen precursors can be employed, along with simple transition metal salts, such as acetates, nitrates or chlorides.…”

Highly active ZIF-8@CNT composite catalysts as cathode materials for anion exchange membrane fuel cells

“…In previous studies, we have tested Fe-and Co-based catalysts in an AEMFC using a 10 μm thick Aemion + AEM, but no reports are available with the Aemion+® 15 μm AEM. 38,75,[77][78][79][80] The Aemion+ AEM (10 μm) consists of repeating units of methylated polybenzimidazoles, which offers high stability in AEMFCs by employing the stericcrowding strategy to stabilise the C-2 position of the imidazole group. 81 Also, the thickness of the AEM plays a crucial role in the efficient migration of OH − ions and H 2 O molecules.…”

MOF-Derived Cobalt Nanoparticles with Dispersed Iron Phthalocyanines as Bifunctional Oxygen Electrocatalysts

“…The extensive use of conventional fossil resources has driven the accelerated advancement of technologies related to clean energy conversion and storage. Among these technologies, rechargeable metal–air batteries have been considered highly promising candidates, primarily owing to their exceptional theoretical energy density, cost-effectiveness, and environmentally friendly nature. − Nevertheless, the sluggish kinetics associated with oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) severely limits their applications on a large scale, emphasizing the increasing need for critical electrode materials with high activity and durability. − Under these circumstances, noble metal-based catalysts (Pt/C, RuO 2 , and IrO 2 ) have been studied as the primary electrocatalysts for the ORR and OER due to their exceptional catalytic performance. , However, their commercial utilization is restricted by high cost and relatively low stability under working conditions. , Significant efforts have thus been dedicated to the development of cost-effective and high-performance bifunctional oxygen catalysts that can efficiently and reliably drive both ORR and OER simultaneously. − …”