Phthalocyanines (Pcs) are a fascinating class of chromophore with wide-ranging applications from liquid crystals to phototherapeutic agents and from photocatalysts to solar cell materials. When synthesized by the statistical tetramerization of substituted phthalonitrile derivatives lower than C2v symmetry, an inseparable mixture of four isomers is commonly formed, with the clear drawback that these isomers have different optical, material, and biological properties.
We recently introduced a regioselective route to C4h functionalized Pcs and have an unpublished method for accessing D2h Pcs. In this project you will develop new synthetic routes to regioregular phthalocyanines and investigate the effect of a regioregular design on their aggregation and self-assembly behaviour. Our hypothesis is that the use of a pure, high-symmetry regioregular Pc, as opposed to a mixture of isomers, will lead to closer and more regular packing and assembly with fewer defects through better tessellation. This will lead to stronger electronic coupling between individual Pcs in a dimer, stack or larger aggregate or structure, which will be investigated using optical spectroscopy. Demonstrating this to be true could lead to the production of higher quality Pc supramolecular architectures and thin-films, which could in turn be beneficial, for example, for improving charge transport in optoelectronic applications.
We are open to discussing the balance of synthetic and spectroscopic aspects of the project and also to discuss other applications of phthalocyanines, fluorescence, bio-imaging, and sensing. Get in touch with Bob Edkins via [Email Address Removed] to discuss your interests.