Bimetal-organic Framework Encapsulated in Graphene Aerogel-grafted Ni Foam: An Efficient Electrocatalyst for the Oxygen Evolution Reaction

Graphical 2D bimetal-organic frameworks : Graphene aerogel can serve as both the “room” for numerous MOFs and the “conductive bridge” to connect MOFs with metal foam. A 2D bimetallic MIL-53(FeNi) encapsulated in graphene aerogel-grafted Ni foam acts as a binder-free electrode for OER, exhibiting remarkable stability in alkaline media. Metal-organic frameworks (MOFs) have been considered as promising platforms for preparing the efficient oxygen evolution reaction (OER) catalysts, but few of them are directly employed as active components due to their poor electrical conductivity. Herein, a lamellar bimetallic MFN (MIL-53(FeNi)) encapsulated in graphene aerogel-grafted Ni foam has been developed (denoted as MFN@GA/NF). The graphene aerogel (GA) provides abundant space for the in-situ growth of MFN and functions as a “bridge” to connect nickel foam (NF) with MFN by virtue of good conductivity. Benefitting from its structural integrity, the obtained hierarchical MFN@GA/NF exhibited excellent OER performances in alkaline media with an overpotential of 250 mV (20 mA cm −2 ) and 326 mV (200 mA cm −2 ), as well as remarkable stability in continuous electrolysis for over 100 h. This work provides a new channel for engineering MOF-based functional materials with featured architectures.