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Item Asymmetric catalysis via spatially separated chiral and catalytic motifs in multicomponent metal-organic frameworks : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatū, New Zealand(Massey University, 2025-11-18) Petters, LudwigModern life without catalysis is inconceivable. Asymmetric catalysts are a special type of catalyst that preferentially produce one of two possible enantiomers over the other. The ability to selectively obtain exclusively one of the possible enantiomers is of highest importance for modern synthetic chemistry. To enable the transfer of chiral information from the catalyst to the reaction substrates, asymmetric catalysts must be chiral. In conventional asymmetric catalysts, the catalytic and chiral motifs are held close together within one single molecule. In this work, we break the design limitation of conventional asymmetric catalysts with a strategy we call ‘remote asymmetric induction’ (RAI). In RAI catalysts, the catalytic and chiral motifs are independent of each other in their design and synthesis. To achieve this, we use the multicomponent metal-organic framework MUF-77 (MUF = Massey University Framework). MUF-77 consists of three chemically distinct linkers that each occupy a specific position in the framework without disorder or randomness. To create RAI catalysts, the catalytic and chiral motifs are individually anchored to the different building blocks of MUF-77. By virtue of the MUF-77 structure, the catalytic and chiral motifs are in close proximity to one another in a catalytic pore, which creates an active site. This enables the transfer of chiral information to the reaction participants. Initially the reaction scope of the RAI catalyst was expanded by screening a variety of RAI-MOFs incorporating different catalytic and chiral functionalities across a range of model reactions. A promising catalyst for one model reaction was identified and investigated in depth. Through systematic modification of important reaction variables, the variation in enantioselectivity of this system was explored. After parameter optimisation, very good to excellent enantioselectivity was achieved. Control experiments confirmed that the origin of enantioselectivity arises from remote cooperative interactions between the functionalities in the active site. The catalysts were then tested for classical performance metrics and a hypothetical transition state within the MOF pore was proposed. This work establishes RAI as an alternative platform to develop high-performing asymmetric catalysts.Item Multicomponent metal-organic frameworks : tailoring platforms for transition metal- and bioelectrocatalysis : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatū, New Zealand(Massey University, 2025) Auer, Bernhard StephanMUF-77 (MUF = Massey University Framework) is a quaternary, multicomponent metal-organic framework (MOF), constructed from three topologically distinct carboxylate linkers and Zn4O secondary building units. Multicomponent MOFs such as MUF-77, constructed from a set of ligands with different geometries, provide a valuable platform for obtaining ordered and programmable pore environments. In this context, they show great potential as recyclable and stable, heterogeneous catalysts. In this work, we looked at the typical MUF 77 synthesis conditions and investigated the formation of additional crystalline phases. Several new MOFs were discovered, including new multicomponent MOFs. We then investigated MUF-77 for the incorporation of transition metal catalysts. The work included ligand and MOF syntheses and synthetic modifications of the frameworks upon MOF formation. We also embedded a Au(III) catalyst within the MUF 77 framework and evaluated its catalytic properties upon installation into the framework. Finally, we shifted our focus to systems comprising MOF and enzyme components for their electrochemical application in layer-by-layer-grafted electrodes. The work extended our library of potential heterogeneous catalysts, showcasing the great potential of multicomponent systems.Item Metal-organic framework (MOF) membranes for gas separations : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatu, New Zealand(Massey University, 2024-04-29) Zhang, YimingThe study presented in this thesis involves the design, preparation and evaluation of metal-organic frameworks (MOFs) for gas separation applications, with a focus on the development of MOF membranes with both high gas permeability and good selectivity. Here, two types of membranes, including crystal glass composite membranes (CGCMs) and mixed matrix membranes (MMMs), were prepared and characterized, followed by a comprehensive evaluation of their performance for CO₂ separation. Separating gases using membranes is appealing due to their efficiency and low energy requirements. Recently, glasses have been discovered that are produced by the melt-quenching of ZIFs. In chapter 2, we propose that useful membranes can be prepared by combining ZIF glasses with MOFs. We prepared these crystal-glass composite membranes by ball milling ZIF-62 with various crystalline MOFs followed by pressing into a tablet, heating to melt the ZIF-62 into a glass, and subsequent cooling. This fabrication process delivers membranes with homogenous dispersion of crystalline MOF particles in a ZIF glass matrix. As an alternative, we show how pre-forming ZIF-62 glass allows membranes to be formed with MOFs with relatively low stability. The resulting crystal-glass composite membranes show ultrahigh CO₂ permeance. MMMs offer great potential for gas separation through the integration of nanofillers into polymers with excellent processability. Among these, MOF-based MMMs have emerged as promising candidates for advanced gas separation applications. However, a major obstacle hindering their performance is the inherent interfacial incompatibility between MOFs particles and the polymer matrix. In this thesis, we present a viable solution utilizing a scalable ball milling approach to address this challenge, specifically targeting the interfacial incompatibility between MUF-16 and the polymer matrix. Significantly, our approach involves the production of MUF-16 with varying crystal sizes through ball milling prior to MMM fabrication. In chapter 3 and 4, we illustrate that the nanosizing of MUF-16 (nsMUF-16) enhances its dispersion within three different polymer matrices (Pebax, 6FDA-DAM and 6FDA-Durene), effectively minimizing non-selective voids around the particles. Importantly, MMMs incorporating nsMUF-16 consistently exhibit superior CO₂ separation performance compared to those utilizing micro-sized MUF-16. Overall, this study highlights a versatile methodology employing engineered approaches to develop high-performance membranes with enhanced interfacial compatibility for gas separation. Furthermore, this approach holds promise for extending the processability of other MOF adsorbents into matrix materials, thereby broadening the scope of potential applications in gas separation technologies. Due to the distinctive structural arrangement of MUF-15, where the phenyl rings of the ipa ligands protrude into the void space, there exists a potential for substituting the ipa ligand with various functional groups. This opens avenues for obtaining analogues of MUF-15. These functionalized variants, denoted as MUF-15-X (with X representing substituents such as F, Br, CH₃, and NO₂), offer the prospect of imbuing MUF-15 with diverse gas sorption properties. Consequently, our interest is piqued to explore the structural characteristics and gas separation capabilities of these analogues across different functional groups. In chapter 5, we present a comprehensive investigation into 6FDA-DAM-based MMMs incorporating MUF-15 and its analogues for CO₂ separation from CH₄. Notably, this study constitutes the pioneering utilization of MUF-15 analogues as fillers in MMMs specifically designed for CO₂/CH₄ separation. It introduces a spectrum of emerging MUF-15 derivatives as potential filler materials for MMM development and underscores the efficacy of pore structure functionalization in augmenting the separation performance of MMMs.Item Isophthalic acid derivative metal-organic frameworks for gas capture and separation : a thesis presented in partial fulfilment of the requirements of the degree of Master of Science in Chemistry at Massey University, Manawatu, New Zealand(Massey University, 2022) Scott, Victoria-JayneGas capture and separation is a relevant, dynamic field of research because gases play a vital role in our society from the synthesis of polymers and plastics to the production of fuel. Furthermore, there is an ever-increasing concentration of greenhouse gases, namely CO₂ and methane, in the atmosphere, which is leading to climate change. Various types of adsorbents and absorption-based methods have been utilized for gas capture and separation, however many of these methods are expensive and have a high energy penalty. Metal-organic frameworks (MOFs) are a class of adsorbents which can be made inexpensively, and they can be recycled with a low energy input, thus making them desirable materials for gas capture and separation. This thesis focuses on MOFs with small pores for gas capture and separation. The MOFs are made with isophthalic acids, which are inexpensive starting materials. The MOFs were found using the Cambridge Structural Database, analysed using a simulation software known as PoreBlazer, and then synthesized for gas adsorption analysis. Many reported synthetic procedures could not be replicated, but this led to the discovery of many new MOF materials. Together with the MOFs that could be reproduced in our laboratory, many MOFs were found with good uptakes and good selectivities for various interesting gas pairs. This thesis not only introduces several new MOFs but shows the variability of using the isophthalic acid ligand core to produce many MOF materials. Overall, several important discoveries of new MOF materials for important gas separations were made.Item Applications of multicomponent metal-organic frameworks : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatū, New Zealand(Massey University, 2021) Lee, Seok JuneMulticomponent metal-organic frameworks (MOFs) comprise multiple organic ligands that are topologically distinct. Each organic ligand is precisely positioned in a highly ordered crystal lattice. These allow tunable pore environments induced by the predictable arrangement of chemical functional groups on multiple ligands. This study was mainly focused on utilising such benefit of multicomponent MOFs. First, a novel concept for asymmetric catalysis was implemented. Sequence-specific polymer synthesis by post-synthetically linking the two ligands in a framework was then covered. Both applications exhibited new approaches that had not been demonstrated in conventional chemical reactions. This study exhibits the possibility of multicomponent MOFs as a great platform for many applications.Item Photophysical and catalytic properties of multicomponent metal-organic frameworks : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatū, New Zealand(Massey University, 2021) Cornelio, JoelMulticomponent metal-organic frameworks (MC-MOFs) are crystalline, porous materials built from multiple geometrically distinct organic ligands. The ligands are located in specific lattice sites in the MOF. The properties of these materials can be tuned by incorporating ligands with functional groups for a desired application. This thesis deals with studying the applications of MC-MOFs named Massey University Frameworks (MUFs) for luminescence, energy transfer, photochromism, and catalysis. Firstly, we obtain white-light emission in MC-MOFs from the combination of blue and yellow luminescence of the ligands. The trends observed in the emission spectra originate from inter-ligand energy transfer interactions. These interactions have been explored further using a variety of crystallographic and spectroscopic techniques including time-resolved luminescence at the nanosecond and picosecond timescales. In another chapter, we have studied photochromism in some MC-MOFs which is caused by light-generated organic radicals. The differences between their radical and non-radical forms has been elucidated using X-ray crystallography. We also research the impact of pore environment on the outcome of an enantioselective intramolecular aldol reaction catalysed by MC-MOFs. Finally, a number of ideas are proposed as part of future work, that take advantage of the multicomponent nature of these materials.Item Synthesis of nanoscale metal-organic frameworks in non-ionic microemulsions : a thesis presented in partial fulfilment of the requirements of the degree of Masters of Science in Nanoscience at Massey University, Manawatu, New Zealand(Massey University, 2020) Craig, Timothy MartinMOFs are a versatile class of porous materials made from metal ions and organic ligands. The structural and functional diversity of these materials allows them to be used in wide variety of applications. However, the mechanisms behind crystal growth are far from fully understood. As a result, control of the MOF particle size has remained largely inconsistent. Several methods have been used to control MOF particle size including microwave assisted synthesis and adjusting the metal: ligand ratio. Recently, researchers have begun to explore the use of microemulsions as an environment to synthesize precise size-controlled nanoscale MOFs. However, this field has been largely unexplored. Herein it is proposed that a non-ionic water/hexanol/Triton X-100/cyclohexane microemulsion can be used as a generic environment for the synthesis of MOF nanoparticles. In chapter 2, microemulsion synthesis was applied to synthesize ZIFs; the most common MOF subclass. ZIF-8 sod was synthesized with a tuneable particle length ranging from 27.3 to 87.3 nm. This was achieved primarily by adjusting the time taken to add the ligand solution to the metal solution. This technique was then applied to synthesize ZIF-67 and Zn-IM MOFs. A relatively rare Zn(IM)₂ neb topology was observed during synthesis. In chapter 3, it was demonstrated that microemulsion synthesis could be utilized to synthesize the protein complexes BSA@ZIF-8 & BHG@ZIF-8. The resulting materials had high loading efficiency values up to ~17%. Furthermore, the particle size could be finely tuned from 69.7 to 87.6 nm and 55.9 to 75.3 nm respectively by adjusting the addition time. In chapter 4, microemulsion synthesis was extended to UiO-66. The newly developed synthesis is both room temperature and does not require the environmentally harmful use of DMF. By altering the addition time or ω₀ value the UiO-66 particles size could be altered from 4.09 to 31.0 nm. Hence, the synthesis of the smallest sample on record was achieved. Finally, in chapter 5, the results of the previous chapters were summarised. It was acknowledged that significant room for reaction parameter optimization exists in all chapters discussed thus far. However, testing all these parameters would be tedious and may not necessarily lead to significant insights. Hence, it was instead proposed that cyro-TEM, SAXS and in situ PXRD are used to monitor the growth of a MOF using either, Zn(IM)₂ neb, ZIF-8 or UiO-66. Such a study on the mechanistic behaviour of MOFs synthesized using microemulsion synthesis would be invaluable to expanding work in this field.Item Hetero-interpenetrated metal-organic frameworks : supramolecular interactions between ligands in metal-organic framework formation : a thesis presented in fulfilment of the requirements of the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatū, New Zealand(Massey University, 2020) Perl, DavidMetal-organic frameworks are an exciting class of materials formed through the self-assembly of their metal ion and organic ligand components into ordered, nanoporous lattice structures whose pore spaces are open to solvent, gas, and other guest molecules. Their consequently high surface areas render them suitable for diverse applications including gas storage, separations, and catalysis. The ability to precisely engineer the chemistry of the pores in framework materials and thus tune their properties is one of their most attractive features. Interpenetration, a phenomenon where multiple lattices are woven through each other, is an important handle on tuning their properties, mediating between pore shapes and volumes, chemistries, and robustness. In this thesis new frameworks are presented where two chemically distinct lattices are interpenetrated, a longstanding target in the field. These frameworks therefore have two orthogonal handles on both pore shape and functionalisation and have been applied to asymmetric organocatalysis by embedding an achiral catalytic site within a chiral pore space. Additionally, some insight is gained into the underlying principles of the formation of complex types of interpenetration through the exploitation of several analogous novel ligands.Item Synthesis of multicomponent metal-organic frameworks and investigations of their physical properties : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatu, New Zealand(Massey University, 2019) Alkaş, AdilMulticomponent metal-organic frameworks (MOFs) are built up from multiple ligands that are geometrically distinct. These ligands occupy specific positions in the MOF lattice. Installing different functionalities at precise locations in the framework is an important step in making MOFs for specific applications. This can be achieved by designing functionalized ligands for multicomponent MOFs. This study was, firstly, focused on design and synthesis of new linkers. The study then covered preparation of a number of quaternary MOFs. Furthermore, the study was focused on the physical and chemical properties of these MOFs, such as their catalytic activity, gas adsorption and fluorescence behaviours.Item Interior decoration of metal-organic frameworks through a thermolabile protecting group strategy : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Chemistry at Massey University, Manawatū, New Zealand(Massey University, 2019) Jameson, HeatherMetal-organic frameworks are porous nanomaterials of modular construction that have shown themselves amenable to different modes of functionalization. Thermolytic deprotection (thermolysis) of incorporated thermolabile protecting groups (TPGs) has been one of these methods applied to tune the chemistry of MOFs and their material properties, accessing otherwise unattainable MOF topologies with enhanced porosity and reactive functionalities of particular interest in gas storage and separation and catalytic applications. In this thesis the TPG post-synthetic modification (PSM) technique is expanded upon in two ways. Firstly, through investigation of mono-and dual-functionalization within a flexible pillar-layer MOF family: localization of the TPG, influence on framework topology and gas sorption characteristics. Secondly, in synthesis of a set of novel ketene-protecting TPG ligands: ligand characterization, and endeavours at MOF incorporation.