Assemblies of Metal-Organic Polyhedra: Synthesis, Properties and Characterization
Date
2019-09-03
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Metal-Organic Polyhedra (MOP) are nanoscale capsule-like supramolecular architectures composed of metal ions and organic linkers. They have well defined cavities depending on the ligand shape and metal-vertex geometry. The thesis concerns MOP composed of 12 copper(II) dimers (Cu24) and 24 isophthalate based linkers forming ~2 nm cuboctahedral structure. The isophthalates can be easily functionalized at 5th position with different chemical groups thereby giving surface functionalization to the Cu24MOPs. They are soluble depending upon the functional groups while retaining the structural integrity in solution. This offers rich solution chemistry and variety of potential applications. In this thesis, the versatility of Cu24MOPs has been utilized to create functional materials. Firstly, the degradation of a Cu24MOP is studied when exposed to water leading to formation of three coordination products at different time intervals (2,3 and 4). This study is crucial given the increasing use of MOPs for different purposes, to understand their outcomes when exposed to ubiquitous humidity/water. Secondly, long alkyl chain functionalized Cu24MOP, half of them having terminal alkenes have been synthesized (5) and utilized to create metal-organic framework (MOF) of different mechanical strength. This was done by cross-linking the MOP units via olefin metathesis and investigating mechanical properties through rheology and nanoindentation. Thirdly, Cu24MOPs functionalized with both polar and non-polar isophthalates were synthesized and the arrangement of linkers on the MOP surface i.e. symmetrical (6) and Janus-type (7 or ampMOP) were analyzed via crystallography and microscopy. Amphiphile-like self-assembly behavior of the Janus MOP was studied thoroughly. Lastly, mixed matrix membranes (MMM) using ampMOP and PEBAX polymer were created for usage in CO2/N2 gas separations. Overall, the thesis provides a reference for exploiting novel properties of MOPs.
Description
Keywords
Citation
Lal, G. (2019). Assemblies of Metal-Organic Polyhedra: Synthesis, Properties and Characterization (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.