Open AccessAqueous-System-Enabled Spray-Drying Technique for the Synthesis of Hollow Polycrystalline ZIF-8 MOF Particles
Author(s) -
Shunsuke Tanaka,
Ryo Miyashita
Publication year - 2017
Publication title -
acs omega
Language(s) - English
Resource type - Journals
ISSN - 2470-1343
DOI - 10.1021/acsomega.7b01325
Subject(s) - zeolitic imidazolate framework , aqueous solution , crystallite , materials science , sodalite , amorphous solid , imidazolate , metal organic framework , adsorption , chemical engineering , zeolite , spray drying , nanotechnology , crystallography , chemistry , organic chemistry , catalysis , metallurgy , engineering
Zeolitic imidazolate framework-8 shares the same topology with sodalite zeolite but consists of Zn nodes bridged by imidazolate linkers to form a neutral open-framework structure. ZIF-8 has been recognized as a unique molecular sieving material with a flexible framework enabling interesting "gate-opening" functionality. Controlling the crystal size and shape is crucial for regulating the structural flexibilities and mass transport properties. The present study demonstrates that an aqueous-system-enabled spray-drying process enables the shape engineering of ZIF-8 with a hollow polycrystalline structure. It is notable that our synthesis route produces an amorphous zinc complex compound, which possesses a continuous random network partially with crystalline fillers, after spray drying followed by an amorphous-to-crystal transition via activation treatment using polar organic solvents. The size of primary ZIF-8 crystals consisting of secondary polycrystals depends on the kind of the organic solvent. The macro-/microscopic structures of hollow polycrystalline ZIF-8 significantly structurally enhanced the adsorption capacity and uptake rate. The large-scale, rapid production and enhanced adsorption performances make this continuous method a very promising candidate for industrial applications and shaping of MOF.