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Fafarman, Aaron T.

Publications and source records attributed to Fafarman, Aaron T..

Methods of forming colloidal nanocrystal-based thin film devices

Methods of forming colloidal nanocrystal (NC)-based thin film devicesare disclosed. The methods include the steps of depositing a dispersion of NCs on a substrate to form a NC thin-film, wherein at least a portion of the NCs is capped with chalcogenocyanate (xCN)-based ligands; and doping the NC thin-film with a metal.

36 MATERIALS SCIENCE↗

Methods for the preparation of colloidal nanocrystal dispersion

Methods of preparing a dispersion of colloidal nanocrystals (NCs) for use as NC thin films are disclosed. A dispersion of NCs capped with ligands may be mixed with a solution containing chalcogenocyanate (xCN)-based ligands. The mixture may be separated into a supernatant and a flocculate. The flocculate may be dispersed with a solvent to form a subsequent dispersion of NCs capped with xCN-based ligands.

36 MATERIALS SCIENCE↗

Methods for preparing colloidal nanocrystal-based thin films

Methods of exchanging ligands to form colloidal nanocrystals (NCs) with chalcogenocyanate (xCN)-based ligands and apparatuses using the same are disclosed. The ligands may be exchanged by assembling NCs into a thin film and immersing the thin film in a solution containing xCN-based ligands. The ligands may also be exchanged by mixing a xCN-based solution with a dispersion of NCs, flocculating the mixture, centrifuging the mixture, discarding the supernatant, adding a solvent to the pellet, and dispersing the solvent and pellet to form dispersed NCs with exchanged xCN-ligands. The NCs with xCN-based ligands may be used to form thin film devices and/or other electronic, optoelectronic, and photonic devices. Devices comprising nanocrystal-based thin films and methods for forming such devices are also disclosed. These devices may be constructed by depositing NCs on to a substrate to form an NC thin film and then doping the thin film by evaporation and thermal diffusion.

36 MATERIALS SCIENCE↗