Fossil fuels currently supply most of the world's energy needs, and however unacceptable their long-term consequences, the supplies are likely to remain adequate for the next few generations. Scientists and policy makers must make use of this period of grace to assess alternative sources of energy and determine what is scientifically possible, environmentally acceptable and technologically promising.

A low molecular weight purely organic Forster resonance energy transfer (FRET) sensitizer system combining multiple chromophores into a single molecule via covalent attachment is designed to adjust the ratio and relative position of the fluorol donor and coumarin acceptor units. A phenyl based scaffold accommodates both FRET partners and is connected to a carboxylic anchor group for adsorption on a semiconductor surface. The functionality of the complete ensemble is demonstrated by UV−vis and luminescence lifetime measurements. The energy and charge transfer dynamics of the FRET assemblies in solution and adsorbed on ZnO nanorods are measured by femtosecond transient absorption spectroscopy. Optical pump THz probe (OPTP) spectroscopy is applied to detect the injected electrons in the ZnO electrode, confirming the full electronic pathway from FRET light harvesting to subsequent charge carrier injection.

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W i t h i n t h e U . S . D e p a r t m e n t of E n e r g y , in t h e Office of E n e r g y Research, the Office of Basic Energy Sciences is responsible for supporting fundamental research in the natural sciences that is needed to accomplish the missions of the Department. The Division of Materials Sciences constitutes one portion of a wide range of research supported by the Office of Basic Energy Sciences. Other programs are administered by the Office's Chemical Sciences, Energy Biosciences, Engineering and