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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 Development of a molecular toolbox for multifunctional lanthanide-based supramolecular materials : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry at Massey University, Albany, New Zealand(Massey University, 2022) O'Neil, AlexUsing simple building blocks to develop functional supramolecular materials is an active area of research. To this extent the use of lanthanide ions (Ln³⁺ to direct supramolecular self-assembly with organic ligands has become a popularised method whereby the interesting photophysical properties of Ln³⁺ can be manipulated by simple modification of the organic architecture. Applications of such systems vary from solar waveguides, OLEDS, molecular sensors, contrast agents, bio-probes, security inks and barcodes. Herein, a synthetic strategy has been developed and investigated to readily functionalise the organic scaffolds 2,6-pyridinedicarboxamide (PDA) and 6-carbamoylpyridine-2-carboxcylic acid (PDC), using 1,2,3-triazole “click” chemistry. Using this approach, we have synthesised and assessed the f-directed self-assembly ability of some novel PDA-based and PDC-based assemblies. Initial studies focused on symmetrical incorporation of the 1,2,3-triazole linker into the PDA motif via side carbonyls. This resulted in the development of four ligand architectures (1-4), which in the presence of Eu³⁺ and Tb³⁺ self-assemble into Ln(L)₃ (CF₃SO₃)₃ (where L = 1-3) luminescent assemblies. While results of the PDA systems were promising, the systems were relatively unstable in competitive solvents, and as a result subsequent systems focused on the unsymmetrical modification of the PDC motif. Incorporation of our synthetic strategy into the PDC motif was straightforward and additionally improved both Ln³⁺ complex stability and emission intensity. Using this approach, amphiphilic ligand 5 and visibly emissive amphiphilic complexes Ln(5)₃ (where Ln = Eu³⁺, Tb³⁺, Sm³⁺ and Dy³⁺) were synthesised. The incorporation of a long alkane chain via the 1,2,3-triazole in ligand 5 allowed for the fabrication of ultra-thin luminescent films by Langmuir-Blodgett (LB) technique resulting in bright visibly emissive monolayer films. Furthermore, mixing of the emissive Ln(5)₃ complexes resulted in tunable emission dependent on the composition in both solution and monolayer film. Following this, single component dual emissive systems Ln(6)₃, [Ln(7)₃](CF₃SO₃)₃ and Ln(8)₃ were developed. This entailed the incorporation of blue emissive 1,8-naphthalimide (6 & 7) and pyrene (8) via the 1,2,3-triazole linker. When complexed with Eu³⁺ it resulted in dual emissive systems which were colour-tunable, changing colour dependent on the excitation wavelength, and in the case of Eu(6)₃ and Eu(8)₃ it results in white emissive solids and solutions. These properties were transferable to thin films, by spin coating techniques. Finally, the synthetic strategy was used in the initial development of multi-nuclear assemblies forming three multitopic ligands (9-11) and initial complexation studies were undertaken.Item Catalysts derived from metal-organic frameworks : 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, 2021) Bandara, W. R. L. NisansalaThe synthesis of atomic-scale catalysts is a blooming field, and these replace the conventional nanocatalysts due to their high atom utilization, selectivity, and unique catalytic activity. Metal-organic frameworks (MOFs) serve as promising precursors for the synthesis of single-atom catalysts (SACs). This study focused on the synthesis of SACs on nitrogen-doped hollow carbon by using MOFs and MOF composites followed by pyrolysis. The synthesis of two SACs namely rhodium SACs (Rh SACs) and cobalt SACs (Co SACs) by different methods, their characterization, and catalysis was explored. Rh SAC synthesized in this work hydrogenates nitroarenes with high consumption and high selectivity. Moreover, Co SAC did little or no hydrogenation of the nitroarenes. Further applications of these SACs were explored by employing them in oxygen reduction reaction (ORR), NO abatement, and Fenton-like catalysis. Moreover, the synthesis of two types of hollow nanoboxes (HNB) namely HNB-1 and HNB-2; using MOFs and MOF composites, their characterization and applications were also investigated. HNB-1 was used to make electrode supercapacitors and it showed comparable activity to activated carbon. Further attempts were made to use HNB-2 as a fluorescence sensor. Finally, several ideas on synthesising SACs and HNBs were proposed as a part of future work.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.