摘要：

A number of major disciplines have separately developed as distinctfields of energy research utilizing nanostructure materials: i.Heterogeneous photocatalysis; ii. Photoelectrochemistry—includingelectrochemical photovoltaic cells; iii. Photochemistry in zeolites andintercalated materials; iv. Photochemistry of thin films andmembranes—including self assembled structures; and v. Supramolecularphotochemistry. Photophysical properties of small particles, in the angstromto nanosized regime—depending on specific material, resulting in bandgap broadening as compared to bulk properties, and corresponding phenomenawith organic dyes as a function of aggregate size having relevance to energyrelated applications are discussed, as are dielectric confinement effectscontrolling the geometric distribution of light absorption within aparticle, aggregate or adsorbed molecular deposit. Synergism among fieldshas emerged, as for example with transition metal oxide photocatalysts andphotoelectrodes, combined with supramolecular spectral sensitizingtransition metal ligand complexes used to harvest light and vectoriallytransfer photo-generated electrons and holes along selected energeticpathways. Two systems have already demonstrated potential for significantlyreducing reliance on fossil fuels and concomitant environmental stress.These are: i. Pollution remediation with wide band gap semiconductingparticulate and nanoporous photocatalysts; and ii. Electrochemicalphotovoltaic cells utilizing nanoporous semiconducting electrodes fabricatedby lightly sintering nanosized TiO2 particulates, followed byspectral sensitization with tri-nuclear ruthenium ligand dyes.Heterojunction contacts between inorganic photoconducting particulates,termed photocatalytic diodes, and three phase systems, termed photocatalytictransistors, have been demonstrated to increase photocatalytic conversionefficiency in catalytic processes and to increase light sensitivity ofanalogous silver halide photographic systems. Research being carried out inlaboratories throughout the world, aimed at improving the efficiency andunderstanding of the multi-disciplinary processes involved are described.Suggested areas of investigation for achievement of short (5 years) andlong term (5–20 years) goals are reviewed.

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