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Facile preparation of low-cost electrocatalysts for efficient oxygen evolution reaction (OER) remains a big challenge. Herein, a novel strategy for ultrafast (20 s) transformation of bulk metal–organic frameworks (MOFs) into ultrathin metal oxyhydroxide nanosheets for efficient OER has been developed. For two isomeric MOFs (FJI-H25Fe and FJI-H25FeCo), only the metastable FJI-H25FeCo bulk can immediately transform into FeCo-oxyhydroxides nanosheets through electric-field assisted hydrolysis. The potential evolution process from MOF bulk to FeCo-oxyhydroxides nanosheets has been investigated in detail. The as-made nanosheets exhibit excellent OER performances, showing an extremely low overpotential of 231 mV at the current density of 10 mAcm-2, a relatively small Tafel slope of 42 mVdec-1, and long-term durability of at least 30 h. This work not only provides a novel strategy for facile preparation of low-cost and efficient OER electrocatalysts, but also represents a new way for preparation of metal oxyhydroxides nanosheets with good crystallinity and morphology, and a fresh method for mild synthesis of nanosized derivatives from MOF materials. [ABSTRACT FROM AUTHOR]

The article focuses on the crystallization of diaquabis(4,4'-bipyridine N,N'-dioxide-κO)-bis(dicyanamido)cadmium(II). The central cadmium ion in the crystal structure is located at an inversion center, coordinated by two nitrogen atoms from dca, two oxygen atoms from bpno and two oxygen atoms from water molecules, in an approximately octahedral geometry. Colorless prismatic crystals of the complex were prepared from the solution by slow evaporation at room temperature. H atoms bonded to C atoms were placed at calculated positions by the help of a riding model.