Mechanochemical dry conversion of zinc oxide to zeolitic imidazolate framework

Abstract

Mechanochemical dry conversion that only uses zinc oxide and an imidazole ligand proved to be effective and reliable for fabrication of a zeolitic imidazolate framework with a polycrystalline grain boundary and a core-shell structure. The zinc oxide crystals are converted into a zeolitic imidazolate framework to a depth of approx. 10 nm below the surface.

Strategies for controlling crystal structure and reducing usage of organic ligand and solvents in the synthesis of zeolitic imidazolate frameworks

“…46 The first attempt to the mechanochemical synthesis of ZIFs was made by Friscic et al [47][48][49] The addition of small amounts of solvents and salts, the so-called ion-and liquid-assisted grinding, is required for the reaction between ZnO and imidazole ligands. 50 Nano-sized ZnO powder (average particle size of 24 nm) and Hmim were added into a ball mill, and then milled under a rotation of 100 rpm. 47 Tanaka et al reported the solventless mechanical dry conversion of ZnO to ZIF-8 without adding any other additives.…”

“…The three main processes take place parallelly 50. The three main processes take place parallelly 50.…”

The Metal–Organic Framework MIL‐53(Al) Constructed from Multiple Metal Sources: Alumina, Aluminum Hydroxide, and Boehmite

“…Recent studies have developed novel and efficient methods for the alternative synthesis of MOFs. [2] These methods include microwave-assisted, [3] mechanochemical, [4] electrochemical, [5] ionothermal, [6] and near-critical water-based [7] strategies. These solvent-minimization and time-saving approaches exhibit valuable advantages for the effective synthesis of various MOFs.…”

Chapter 7. Ball-milling Mechanochemical Synthesis of Coordination Bonds: Discrete Units, Polymers and Porous Materials

“…For larger ZnO particles, or their agglomerates, the mechanochemical reaction leads to the formation of particles consisting of a core of zinc oxide surrounded by a shell of ZIF-8 (Figure 7.14d). 105 …”

“…73 Overall, the several existing scanning electron microscopy (SEM) studies indicate that coordination polymers and MOFs prepared by LAG or ILAG will exhibit morphologically well-developed crystals with sizes in the range 100 nm-1 mm. The, so far, only systematic SEM study of particle development 105 during mechanochemical synthesis of MOFs has been conducted for slow (up to 240 h milling) neat grinding of ZnO and 2-methylimidazole to form ZIF-8. The study revealed that the transformation of ZnO particles into ZIF-8 can penetrate as far as 10 nm below the surface of the reactant oxide particle.…”