ZnO as an Efficient Nucleating Agent for Rapid, Room Temperature Synthesis and Patterning of Zn-Based Metal–Organic Frameworks

Abstract

The use of ZnO particles as efficient agents for seeding, growing, and precisely positioning metal−organic frameworks (MOFs) is described. Ceramic seeds have been successfully used for the preparation of Zn-based MOFs with a number of different carboxylic acids: terephthalic acid, 2-aminoterephthalic acid, 1,3,5-benzenetricarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 4,4′-biphenyldicarboxylic acid. In situ synchrotron small-angle X-ray scattering and electron microscopy experiments were employed to determine the effect of the concentration of ZnO nanoparticles, temperature, and time on MOF growth. Under optimized conditions, MOF crystals were found to form in several minutes. This unprecedented capacity to seed MOF formation was used to control the growth of crystals in precise locations. Accordingly, we employed this seeding technique to position porous MOF crystals on paper strips (lateral flow), or within glass and PDMS microchannels (120 μm width and 100 μm height). These data demonstrate that ZnO nanoparticles are versatile seeding agents for the growth of porous crystals in a number of different microfluidic platforms.

ZnO as an efficient nucleating agent and morphology template for rapid, facile and scalable synthesis of MOF-46 and ZnO@MOF-46 with selective sensing properties and enhanced photocatalytic ability

“…36-1451). 20 They also used ZnO nanoparticles as seeds for the heterogeneous nucleation of IRMOF-3, which they synthesized by using Zn(NO 3 ) 2 ·6H 2 O as Zn 2+ source and combination of the conventional precursors for preparation of IRMOF-3 including metal salt and organic ligand with ZnO. In this study, the quantitative conversion of zinc oxide into MOF-46 at room temperature was successfully performed.…”

“…Furthermore, various metal sources (for example, metal oxides, hydroxides, and acetates) have been used for MOF synthesis because of their low cost and safety. 20 In addition, other groups used ZnO nanoparticles with various morphologies as Zn 2+ ions and/or growth template to synthesize ZnO@ZIF-8 core-shell structures. The conversion of Cu(OH) 2 into HKUST-1 could be carried out at room temperature and was suitable for large scale production.…”

Application of metal and metal oxide nanoparticles@MOFs

“…MOFs have shown great potential for the removal of carcinogenic polycyclic aromatic hysdrocarbons (PAHs), heavy metals, pesticides, dyes, radionucludes and other toxic chemicals [159][160][161][162][163][164][165]. Introducing additional functionality via magnetic nanoparticles can be achieved by synthesising magnetic framework composites (MFCs) [166].…”

Facile formation of ZIF-8 thin films on ZnO nanorods

“…This method is often performed using metal oxide powders, with the aim of complete conversion of the oxide to the desired MOF. 28,29,32,33 Ameloot et al have recently used this method to form coatings of ZIF-8 on zinc oxide nanostructures. 34 The main advantages of using a molten linker for the formation of MOF thin films are the lack of solvent, the ability to re-use unreacted linker and shorter synthesis time with a full surface coverage achieved in less than an hour in contrary to other methods that rely on a longer synthesis time of a day or more.…”