UCLA

Chapter 1 provides an overview of the background and history of graphene nanoribbon synthesis. Different edge structures and heteroatom functionalities are described, as well as on-surface and in-solution bottom-up synthetic methods. A novel solid-state approach developed by our group is introduced. An overview of conjugated polymers and conjugated polyelectrolytes is also included. Chapter 2 describes the conversion of 1,4-bis(3’-quinolyl)-1,3-butadiyne to potential graphene nanoribbon (GNR). The monomer undergoes topochemical polymerization to form the corresponding polydiacetylene (PDA). Heat treatment of the PDA results in cyclized products, which are characterized using various spectroscopic techniques. Computational studies on small-molecule models investigate the mechanism of the subsequent cyclization process.Chapter 3 describes the application of trans-enediynes as molecular models of a monomer unit within a polydiacetylene framework. The synthesis of multiple variations of this scaffold is demonstrated, and the potential exploration of lowering the Hopf cyclization barrier via gold catalysis, both on-surface and in solution, and via ring strain reduction via norbornadiene inclusion is discussed.Chapter 4 explores a family of amphiphilic semiconducting polymers with a poly(cyclopentadithiophene-alt-thiophene) (PCT) backbone. Monomers with neutral oligoether sidechains modulate the anionic charge density of sulfonated sidechains. The effects of oligoether sidechain inclusion on structure, electronic properties, and doping are explored for water-soluble polymers. For the non-water-soluble polymers, the structures in both solution and the solid state are examined.