A novel Zn4O-based triazolyl benzoate MOF: synthesis, crystal structure, adsorption properties and solid state 13C NMR investigations

Abstract

The newly synthesized Zn₄O-based MOF ³_∞[Zn₄(μ₄-O){(Metrz-pba)₂mPh}₃]·8 DMF (1·8 DMF) of rare tungsten carbide (acs) topology exhibits a porosity of 43% and remarkably high thermal stability up to 430 °C. Single crystal X-ray structure analyses could be performed using as-synthesized as well as desolvated crystals. Besides the solvothermal synthesis of single crystals a scalable synthesis of microcrystalline material of the MOF is reported. Combined TG-MS and solid state NMR measurements reveal the presence of mobile DMF molecules in the pore system of the framework. Adsorption measurements confirm that the pore structure is fully accessible for nitrogen molecules at 77 K. The adsorptive pore volume of 0.41 cm³ g⁻¹ correlates well with the pore volume of 0.43 cm³ g⁻¹ estimated from the single crystal structure.