Mimicking Natural Photosynthesis

From a fundamental viewpoint, carbon dioxide reduction is a model reaction which can help us to understand better the mechanism of natural photosynthesis.11 Development of artificial photosynthetic systems, by mimicking functions of green plants, is one of... 

Photophysical processes are commonly encountered and can participate in such important phenomena as energy harvesting (antenna effect), which is the basis for natural photosynthesis and artificial systems mimicking it [4-21] (see below). 

The p>orphyiins have attracted considerable attention because are ubiquitous in natural systems and have prosp>ective applications in mimicking enzymes, catalytic reactions, photodynamic therapy, molecular electronic devices and conversion of solar energy. In particular, munerous p>orphyrins based artificial light-harvesting antennae, and donor acceptor dyads and triads have been prepared and tested to improve our understanding of the photochemical aspect of natural photosynthesis. 

The second article also deals with PET in arranged media, however, this time by discussing comprehensively the various types of heterogeneous devices which may control supramolecular interactions and consequently chemical reactions. Before turning to such applications, photosynthetic model systems, mainly of the triad type, are dealt with in the third contribution. Here, the natural photosynthetic electron transfer process is briefly discussed as far as it is needed as a basis for the main part, namely the description of artificial multicomponent molecules for mimicking photosynthesis. In addition to the goal to learn more about natural photosynthetic energy conversion, these model systems may also have applications, which, for example, lie in the construction of electronic devices at the molecular level. 

As a new type of electron relay, which is able to penetrate lipid membranes, we tested menaquinone (MQ, Fig. 7). Compounds of this type were not utilized earlier for artificial vesicle-based systems. However, these mimick the functioning of the Z-scheme of natural plant photosynthesis (see Figs 9 and 12). Indeed, the activity of MQ in the redox processes in a lipid bilayer membrane was revealed. However, the quantum yield of the transmembrane electron transfer from a CdS nanoparticle in the inner cavity to a CdS nanoparticle on the outer membrane surface with the participation of MQ appeared to be very low and did not exceed 0.2-0.4%. 

Artificial photosynthesis is mimicking of natural process of photosynthesis but with the use of photocatalysts. 

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