Photocatalysis supramolecular

I/2S2O8 electron-conducting walls. Molecular engineering of such microreactors nowadays is one of the most fascinating areas of basic research in supramolecular photocatalysis. 

Within the context of supramolecular devices, re-emission of the radiation by luminescence is of interest in sensing and signalling applications, while chemical reactions are of interest in applications such as molecular switches and photocatalysis. Strictly speaking absorption and re-emission type processes are termed molecular photophysics while light-induced chemical reactions or chemical processes are termed photochemistry . 

Transition metal polypyridine complexes are highly redox-active, both in their electronic ground- and excited states. Their electron transfer reactivity and properties can be fine-tuned by variations in the molecular structure and composition. They are excellent candidates for applications in redox-catalysis and photocatalysis, conversion of light energy into chemical or electrical energy, as sensors, active components of functional supramolecular assemblies, and molecular electronic and photonic devices. 

Pemberton BC, Barooah N, Srivatsava DK, Sivagaru J. Supramolecular photocatalysis by confinement-photodimerization of coumarins within cucurbit[8]urils. Chem Commun 2010 46 225-7. 

In this article we illustrate a number of intriguing aspects of the photophysics of polynuclear complexes, including some which are relevant to photocatalysis, using selected examples from oiff own recent experimental work. Recent reviews are available which provide a more complete coverage of the field [16,17]. To facilitate the discussion, some general concepts concerning supramolecular systems and intercomponent transfer processes will first be recalled. 

Although the development of antenna-sensitizer devices for the spectral sensitization of semiconductors might have some practical impact, it would clearly be unrealistic to consider most of the work described in this article of direct relevance to photocatalysis. It seems likely, however, that the need for increasing efficiency and selectivity will lead towards the development of complex photocatalytic systems of supramolecular nature. Thus, further fundamental studies on ways to control and direct photoinduced energy and electron transfer processes in supramolecular systems seem to be worthwhile. 

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