The first of the projects in this theme explores the exciting possibilities that arise from allowing molecules and nanoparticles to self-assemble into photo-active devices and coatings. It is being carried out by Dr Hadi Zareie, Dr Andrew Ford, Dr Mike Ford and Prof. Michael Cortie. At the heart of the project is the concept that light falling onto a nanoscale tunnel junction can be exploited to modulate an electric current, or even to generate one. The former idea is the focus of the work of Dr H. Zareie, while the latter is largely the subject of Dr McDonagh's ARC Fellowship.However, the overarching project binds many individuals' work together: McDonagh suggests and synthesises candidate molecules; Zareie makes and characterises coatings and devices from them; Ford (and PhD student R. Hoft) provide fundamental calculations of their conformation and relative conductivity; Cortie provides the analytical model and software for fitting, analysing and interpreting the resulting tunnelling curves. However, even more interesting systems, based for example on the anthracene molecule (shown above) also beckon.
The second project in this vein is to investigate new dyes as sensitisers for dye-sensitised solar cells which is primarily the research aim of the ARC Fellowship of McDonagh. Similar molecules to those used in the light sensitive tunnel junctions are of interest. The first stage of the project has been a comparison between the properties of ruthenium phthalocyanine and ruthenium naphthalocyanine dyes. Work has shown that the phthalocyanine complexes may be readily synthesised, but the naphthalocyanine analogs are highly insoluble and thus unsuitable for further investigation in their current form. Complexes bearing peripheral tertiary butyl groups as solubilising groups are therefore being synthesised in an effort to overcome this limitation. The availability of more soluble complexes will enable investigation of not only the new monomeric compounds, but also of new dimeric compounds where the phthalocyanine or naphthalocyanine complexes will act as antennas to capture photons.