Processing and patterning of metal organic frameworks and metal organic gels

Akinola, Taiwo Oluwaeseun

Abstract

Metal Organic Frameworks (MOFs), due to their unique properties, have attracted significant research interest in diverse areas such as drug delivery, gas adsorption catalysis and bio-sensing. Although these materials have valuable attributes for future developments, the ability to control their functional properties to precise locations is important for potential applications. Also, the investigation and application of MOF structures has generally been at molecular level limiting their use for large scale industrial applications. Metal Organic Gels (MOGs) are emergent soft materials having both metal-organic framework (MOF) and gel characteristics such as flexibility, varying pore sizes and tunable porosity. These soft materials are of interest as they can easily be processed for various applications in more efficient ways than MOFs. This project aims to discuss the fabrication processing techniques employed for maximizing metal-organic composites properties and prospects for various applications.

Here, we present the use of coatings and lithographic techniques that enable MOF positioning and precise localization of NH₂-MIL-53 (Al) microcrystals on Anodised Aluminium Oxide (AAO) membrane. The advantages and limitations of each reviewed technique for the control of MOFs positioning are highlighted. X-ray and SEM measurements were used for the identification and location of the MOF crystal on the membrane. Also, the synthesis of MOGs under different conditions, factors affecting the gel properties, and how they can be photo-polymerized for processing at large scale dimensions were looked into.

Results obtained using lithographic techniques for patterning NH₂-MIL-53 (Al) microcrystals on AAO showed successful patterning but had limitations in patterning MOF crystal growth when a modulator was introduced. Mil-68 MOG was produced by using Indium metal ion salt with H₃BTC ligands. This was of primary focus due to its thixotropic properties, i.e. shearing and reforming to its original shape after applied force is removed. These thixotropic properties make the material versatile because it can potentially be processed into different shapes with the possibility of introducing polymerizable materials into the gels for crosslinking.

Citation

Akinola, T. O. (2016). Processing and patterning of metal organic frameworks and metal organic gels. (Thesis). University of Hull. Retrieved from https://hull-repository.worktribe.com/output/4218967

• Thesis Type: Thesis
• Deposit Date: Feb 13, 2017
• Publicly Available Date: Feb 23, 2023
• Keywords: Chemistry
• Public URL: https://hull-repository.worktribe.com/output/4218967
• Additional Information: Department of Chemistry, The University of Hull
• Award Date: Sep 1, 2016