Long Chain Derivatives of Sensitizer or Acceptor Relays

The fact that by suitable design of the system, micelles can be made to serve as a carrier for either the oxidized sensitized or the reduced relay has been exploited recently to achieve significant charge separation with amphiphilic viologen derivatives. Consider, for example, the case where the derivative N-tetradecyl N-methyl-viologen is employed as an electron relay. In the oxidized state this compound exhibits a pronounced hydrophylic character while in the reduced state it has hydrophobic properties. 

7x10 %. The absorbance at 890 nm reflects the behaviour of the triplet state while that at 600 nm is characteristic for C 2 MV and ZnTMPyP . The decay of the triplet state is accompanied by the formation of redox products (oscillogram b) which, however, undergo rapid back reaction. In marked contrast to this behaviour stand the results obtained in the presence of cationic micelles (cetyl trimethyl ajnmonium chloride). As is apparent from oscillogram c the forward electron transfer goes here to con5)letion without subsequent intervention of the back reaction. The detailed kinetic analysis shows that CTAC micelles retard the reverse electron transfer by at least a factor of 1000. 

LIGHT INDUCED CHARGE SEPARATION BY FUNCTIONAL MICELLAR ASSEMBLIES 

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