This thesis is an exploration of the synthesis and characterisation of novel selenophene-containing conjugated materials. Conjugated materials containing thiophene units are well-known and offer many exciting applications in OPV, OTFT, and flexible-electronics devices. Theory and some studies suggest that replacing thiophene units with selenophene could potentially improve optical and electronic properties of interest to device performance.
This thesis comprises:
• An introduction detailing the potential interest in selenophene-containing materials and the state of current research.
• An investigation into the Stille polymerization process on a known thiophene-based polymer, PBTTT, testing the limits of Stille polymerization’s effectiveness and the extent to which Stille polymerization can be optimized, as well as investigating the effect of alkyl chain length on the properties of a known polymer.
• A systematic investigation into the effects of replacing thiophene with selenophene on the backbone of a known thiophene-based polymer, poly(terthiophene), and also selenium-bearing analogues of other well-studied polymers, showing how increasing selenophene incorporation affects properties relevant to device performance.
• The synthesis and characterisation of a novel high-performance low-bandgap polyselenophene featuring DPP units, including a discussion on the synthesis of DPP-functionalised selenophene.
Approaches for developing novel fused selenophene-containing materials including issues with functionalising selenophenes, the synthesis of several potentially useful intermediates, the use of a new selenium-transfer reagent, and the successful synthesis and characterisation of three novel fused selenophene-containing systems.