Nanomaterial Development for Polymeric Solar Cells

Photoactive nanomaterials are being investigated as multifunctional additives in polymeric photovoltaic devices. Polymer photovoltaic devices which rely solely on photon absorption by the conducting polymer are bandgap-limited (typically > 2 eV) with regard to the solar spectrum. Therefore, nanomaterials with optical absorption below the conducting polymer bandgap can allow composite devices to absorb a larger portion of the solar spectrum. In addition, nanomaterials may play a role in polymer exciton disassociation and transport. We have investigated the use of rare-earth-doped oxide nanoparticles to absorb light in the lower energy region of the solar spectrum, and "up-convert" photons to energies above the polymer bandgap. In addition, we will highlight the synthesis of novel semiconducting quantum dots (QDs) namely, InSb, for absorption in the ideal region of the solar spectrum. Spectroscopy will be provided for both types of materials in addition to the photovoltaic performance of devices incorporating various up-converting nanoparticles. The prospect of coupling single-walled carbon nanotubes to the various up-converting nanoparticles and QDs will be discussed in terms of their previously demonstrated utility in prototype devices