Investigation of Single-Metal Fe-Based Metal–Organic Framework as an Electrocatalyst for a Rechargeable Zinc-Air Battery

With the advantage of high protection and energy density, the zinc-air battery (ZAB) has shown potential for practical applications in energy research. Metal–organic frameworks (MOFs) are being explored as bifunctional alternatives to replace precious metals. In this work, a new MIL-88B(Fe) MOF was developed and investigated for a rechargeable ZAB. The MOF catalyst was characterized to determine its structure, morphology, pure composition, and porosity. The oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) performance was also examined in alkaline solutions with O₂ and N₂ purging, respectively. The zinc-air cell so developed exhibits good performance with a power density of 101 mW cm^‑2 at 65 mA cm^‑2 current density. The rechargeable Fe-MOF ZAB also shows high cyclic stability with minimum fluctuation at 5 mA cm^‑2 for 500 cycles. The observed results prove that Fe-MOF is a promising catalyst for ZABs.