Rational Synthesis of Metal-Organic Framework Nanocubes and Nanosheets Using Selective Modulators and Their Morphology-Dependent Gas-Sorption Properties

Nanocubes and nanosheets of [Cu-2(ndc)(2)(dabco)](n) metal-organic framework (ndc 1,4-naphthalene dicarboxylate; dabco = 1,4-diazabicyclo[2.2.2]-octane) were synthesized by using simultaneously acetic acid and pyridine or only pyridine, respectively, as selective modulators. This approach can tailor crystal growing on different directions for the size- and shape-controlled synthesis of metal-organic framework (MOF) nanocrystals whose structure is composed of two or more types of linkers using selective modulators. These MOP nanocrystals exhibit high crystallinity and higher CO2 uptakes compared to that of the bulk MOF material or of the [Cu-2(ndc)(2)(dabco)](n) nanorods generated by using only acetic acid as the selective modulator, which may be due to the morphology effect on their gas sorption properties.