Strategic Design of Metal Organic Frameworks for Hydrogen Storage Applications

Abstract

This thesis describes the synthesis, structural chemistry, and functional behaviour of a diverse range of metal-organic frameworks (MOFs), with a primary focus on topological control and hydrogen storage performance. The work in this thesis is concerned with using MOFs industrially, and attempts to better understand the issue of reproducibility and replicability in MOF syntheses and how to modify the synthetic conditions to better target specific phases. A key theme of the work is the inclusion of 2,1,3-benzochalcogenadiazole moieties, which facilitates a study of the effect of isovalent substitution of O, S, and Se in their structures, and the resulting influence on framework topology and hydrogen adsorption capacity. A number of unexpected and new framework isomers were discovered in this work including several that were found to adopt novel topologies. This thesis focuses strongly on investigating the link between the design of the ligand and its corresponding conformational flexibility and how this can be used to rationalise the emergence of varied framework isomers. It is hoped that these fundamental investigations will contribute to the rational design of ligands that enable obtaining MOFs with targeted topologies, pore geometry, and functionality, which will ultimately lead to the development of industrially relevant MOFs for hydrogen storage and other applications.