In order for nanoparticles to be implemented in solid state devices, we need methodologies that permit them to be linked together – with each other, or to another nanocomponent – while still maintaining the unique size-dependent properties of the individual building blocks. Sol-gel methodologies represent a tried and true way of linking particles together in solution, without intervening ligands, into open 3-D architectures with through-connected pore volumes. These gels can be dried and subsequently processed to form dense nanostructures (xerogels) or highly porous nanostructures (aerogels). This approach has been extensively exploited for oxide materials, but these tend to be insulators or large bandgap semiconductors, limiting applications. We have begun to develop sol-gel strategies that can be applied to other materials, most notably metal chalcogenides, for the preparation of electronically linked semiconducting nanostructures with bandgaps from the IR to the UV (Mohanan et. al., Science., 2005, 307, 397-401,10.1126/science.1106525). These materials are expected to be uniquely poised for application in photovoltaic, sensing, and thermoelectric devices
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