Introduction
Metal–organic frameworks, also known as coordination poly- mers, are a fascinating class of hybrid porous crystalline materials made by linking metal-containing units with organic linkers using strong bonds.1 Their unique features, including high porosity, large internal surface area, intricate porous structure, diversity and tailorable chemistry, make them very attractive for numerous applications.2 Nanoscale metal–organic
frameworks (NMOFs), where the sizes of well-dened MOFs are
reduced to micro- and nano-scales, show improved properties when compared to their bulk counterparts.3 Their potential applications can be signicantly extended owing to the superior adsorption kinetics of guest species and their dispersible nature which is distinct from bulk crystals.3