Metal oxide semiconductors can be made metallic by doping with heterovalent ions at high concentration. Our work explores the plasmonic properties of such transparent conducting oxides in the form of chemically synthesized nanocrystals.
In thin films of these nanocrystals, we showed that their plasmon absorption features can be dynamically tuned over an extraordinary range of near infrared frequencies through electrochemical modulation. This phenomenon holds promise for a new breed of smart, energy-saving window coatings.
Now, by fabricating nanocrystal-in-glass inorganic nanocomposite materials from nanocrystals, we are developing a class of materials wherein the individual components and their interfaces are both essential in defining functionality. The direct bonding of nanocrystals to glass at the interfaces substantially perturbs the amorphous structure and can enhance ionic transport.
As a result, our composite electrochromic thin films uniquely exhibit independent control of visible and near infrared transmission and their optical contrast is enhanced about 5 times.