A General Method to Ultrathin Bimetal-MOF Nanosheets Arrays via In Situ Transformation of Layered Double Hydroxides Arrays

Small. 2019 Feb;15(6):e1804761. doi: 10.1002/smll.201804761. Epub 2019 Jan 15.

Abstract

Structure engineering of ultrathin metal-organic framework (MOF) nanosheets to self-supporting and well-aligned MOF superstructures is highly desired for diverse applications, especially important for electrocatalysis. In this work, a facile layered double hydroxides in situ transformation strategy is developed to synthesize ultrathin bimetal-MOF nanosheets (BMNSs) arrays on conductive substrates. This approach is versatile, and applicable to obtain various BMNSs or even trimetal-MOF nanosheets arrays on different substrates. As a proof of concept application, the obtained ultrathin NiCo-BDC BMNSs array exhibits an excellent catalytic activity toward the oxygen evolution reaction with an overpotential of only 230 mV to reach a current density of 10 mA cm-2 in 1 m KOH. The present work demonstrates a strategy to prepare ultrathin bimetal-MOF nanosheets arrays, which might open an avenue for various promising applications of MOF materials.

Keywords: arrays; bimetal-metal-organic frameworks (MOFs); layered double hydroxides (LDHs); nanosheets; oxygen evolution reaction (OER).