Facile preparation of nanocubes zinc-based metal-organic framework by an ultrasound-assisted synthesis method; precursor for the fabrication of zinc oxide octahedral nanostructures

Abstract

Synthesis of metal-organic framework (MOF) materials via ultrasound (US) irradiation involves shorter reaction times and offers enhanced control of particle size and morphology compared to conventional electric (CE) heating. Nanocubes of an interpenetrated pillared-layer Zn(II) metal-organic framework, [Zn2(NH2-BDC)2(4-bpdh)]·3DMF (TMU-16-NH2) (NH2-BDC=amino-1,4-benzenedicarboxylate, 4-bpdh=2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene, DMF=N,N-dimethylformamide), have been synthesized by US process and characterized by Field Emission Scanning Electron Microscopy (FE-SEM), powder X-ray diffraction, thermogravimetric analysis (TGA), elemental analysis and FTIR spectroscopy. The role of initial reagent concentrations and power levels of US irradiation and also reaction time, on size and morphology of nanostructure TMU-16-NH2 have been studied. Moreover, ZnO octahedral nanoparticles were simply prepared through direct pyrolysis of the TMU-16-NH2 nanocubes asa precursor at 520°C without any surfactant or capping molecules.