Tailoring Metal-Organic Frameworks and Derived Materials for High-Performance Zinc-Air and Alkaline Batteries

Developing multifunctional materials from earth-abundantelementsis urgently needed to satisfy the demand for sustainable energy. Herein,we demonstrate a facile approach for the preparation of a metal-organicframework (MOF)-derived Fe2O3/C, compositedwith N-doped reduced graphene oxide (MO-rGO). MO-rGO exhibits excellentbifunctional electrocatalytic activities toward the oxygen evolutionreaction (eta(j=10) = 273 mV) and the oxygen reductionreaction (half-wave potential = 0.77 V vs reversible hydrogen electrode)with a low Delta E (OER-ORR) of 0.88V in alkaline solutions. A Zn-air battery based on the MO-rGOcathode displays a high specific energy of over 903 W h kg(Zn) (-1) (similar to 290 mW h cm(-2)), anexcellent power density of 148 mW cm(-2), and an open-circuitvoltage of 1.430 V, outperforming the benchmark Pt/C + RuO2 catalyst. We also hydrothermally synthesized a Ni-MOF that was partiallytransformed into a Ni-Co-layered double hydroxide (MOF-LDH).A MO-rGO||MOF-LDH alkaline battery exhibits a specific energy of 42.6W h kg(total mass) (-1) (106.5 mu Wh cm(-2)) and an outstanding specific power of 9.8kW kg(total mass) (-1) (24.5 mW cm(-2)). This work demonstrates the potential of MOFs andMOF-derived compounds for designing innovative multifunctional materialsfor catalysis, electrochemical energy storage, and beyond.