In recent years the field of organic semiconducting materials has seen rapid growth and development, with keen interest from both industrial and academic research. In the early stages of development, much of the performance improvements were due to increasingly complex device fabrication and processing methods. Research focused greatly on improving known semiconducting materials such as PPV, PT or PAC. Whilst these materials formed a strong foundation for early research, recent findings suggest that they do not possess the optimum chemical properties in order to achieve ultra-high efficiency devices. As such many research groups are now focusing efforts to develop sophisticated building blocks for incorporation into conjugated macromolecules and polymers. In order for these building blocks to find use as electronic materials, it is important to understand the intrinsic properties of each component and use these to derive effective structure-property relationships for use as tools in creating materials which are tailored to a particular role.Chapter 1 includes a summarized description of band theory and the underlying physics of organic semiconducting materials, followed by a discussion of the recent technologies within the field, in particular donor-acceptor type macromolecules and polymers and their related device structures.Chapters 2, 3 and 4 then present novel 4,8-benzobisthiazole (BBT) containing analogues and their incorporation into functional electronic devices. Chapter 2 discusses the synthesis and functionalization of the unit BBT, and development of an orthogonal conjugation pathway. The effect of non-covalent heteroatom interactions - utilized to induce molecular planarity - are then discussed. Building on from Chapter 2, Chapter 3 discusses the synthesis, characterization and device applications of highly-planarised, 4,8-BBT containing polymeric materials.Furthermore, Chapter 4 discusses the synthesis, characterization and device applications of 4,8-BBT containing, donor-acceptor polymers synthesised analogously to that of literature 2,6-BBT polymers. Comparison of physical and electrochemical properties, as well as device performance has been conducted and utilised to confirm the beneficial characteristics of the 4,8-orientation vs. the traditional 2,6-substitution.
|Date of Award||1 Apr 2015|
- University Of Strathclyde
|Sponsors||University of Strathclyde & EPSRC (Engineering and Physical Sciences Research Council)|
|Supervisor||Robert Martin (Supervisor)|