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The Technology - Advanced
Computational physics calculations have predicted that the ideal TE material will consist of a material with a delta function density of states distributed uniformly in the material. This unnatural material configuration can be approximated via the use of quantumly confined semiconductor nanocrystals that are self-assembled to make a nanocomposite. The density of states is greatly reduced in a quantum confined nanocrystal. This occurs when the physical size of the semiconductor nanocrystal is smaller than the natural electron-hole Bohr radius. For traditional TE materials, this translates to sizes from 5nm - 25nm or so. We have spent the last decade creating nanomaterials that are in the quantum confined regime but we only recently discovered a secret that allows them to be useful for TE applications.
In the past, colloidally grown nanocrystals have been coated with organic surface ligands as part of the synthesis process. These organics are nearly impossible to remove completely and lead to very poor electrical conductivity which defeats any of the benefits of the material. Hence, great care must be taken to ensure that the electrical pathways between particles are clear while retaining quantum confined properties. At Evident, we use inorganic surface ligands to create the nanostructure as a way to avoid the problems that have plagued nano TE research over the last few years. One small step for Evident; one giant leap for TE.

