High Efficiency, Easy-to-Manufacture Engineered Nanomaterials for Thermoelectric Applications

Leveraging the successful Phase I SBIR program, a 24-month effort is proposed to optimize and demonstrate a high thermoelectric Figure-of-Merit (ZT) nanocrystal quantum dot (NQD) thermoelectric (TE) material, which will have thermal efficiency properties far better than traditional bulk thermoelectric materials. In the proposed work, a series of TE devices will be fabricated from solidified NQD films formed from colloidally synthesized NQDs using consolidation and second phase precipitation. The increase of ZT, is dependent on quantum confinement of electrons and holes, as well as the phonon dynamics and transport of the materials. If the size of a semiconductor is smaller than the mean free path of phonons and larger than that of electrons or holes, one can reduce thermal conductivity by boundary scattering without affecting electrical transport. Although charge transport in thermoelectricity is almost monoenergetic (energy levels within a few kT around the Fermi energy), heat transport by phonons is broadband over the Brillouin zone. The significance of the opportunity is the ability to colloidally-manufacture, high performance, conformal, thin film TE materials, free from the lattice and other constraints of MBE growth.