摘要:
The presently disclosed subject matter provides processes for preparing nanocrystals, including processes for preparing core-shell nanocrystals. The presently disclosed subject matter also provides sulfur and selenium compounds as precursors to nanostructured materials. The presently disclosed subject matter also provides nanocrystals having a particular particle size distribution.
摘要:
Embodiments of the present disclosure provide for methods of making quantum dots (QDs) (passivated or unpassivated) using a continuous flow process, systems for making QDs using a continuous flow process, and the like. In one or more embodiments, the QDs produced using embodiments of the present disclosure can be used in solar photovoltaic cells, bio-imaging, IR emitters, or LEDs.
摘要:
A continuous flow reactor for the efficient synthesis of nanoparticles with a high degree of crystallinity, uniform particle size, and homogenous stoichiometry throughout the crystal is described. Disclosed embodiments include a flow reactor with an energy source for rapid nucleation of the procurors following by a separate heating source for growing the nucleates. Segmented flow may be provided to facilitate mixing and uniform energy absorption of the precursors, and post production quality testing in communication with a control system allow automatic real-time adjustment of the production parameters. The nucleation energy source can be monomodal, multimodal, or multivariable frequency microwave energy and tuned to allow different precursors to nucleate at substantially the same time thereby resulting in a substantially homogenous nanoparticle. A shell application system may also be provided to allow one or more shell layers to be formed onto each nanoparticle.
摘要:
A synthetic method of fabricating highly crystalline and uniform nanoparticles of metal sulfides, doped metal sulfides, and multi-metallic sulfides disclosed, using no-toxic and inexpensive reagents. A typical synthetic method comprises the steps of, synthesis of metal-surfactant complexes from the reaction of metal precursors and surfactant, addition of sulfur reagent to the solution containing said metal-surfactant complexes followed by heating to high temperature, aging at that temperature to produce metal sulfide nanoparticles and completing the formation of synthesis of nanoparticles metal sulfides and multi-metallic sulfides by adding a poor solvent followed by centrifuging.
摘要:
Quantum dots of a metal or metal compound are made by a method of providing a solution in an evaporable solvent at a predetermined concentration of a chosen metal and forming droplets of the solution of a substantially uniform predetermined size. The droplets are thereafter brought into contact with a gas phase reagent thereby forming the metal or metal compound quantum dots desired. The solvent may be removed before, during or after the contacting of the droplets with the gas phase reagent. The metal or metal compound quantum dots so formed are deposited on a substrate. The quantum dots may be contained within a polymer as a film. By control of the concentration of the solution and the size of the droplets the size of the quantum dots may be closely controlled.
摘要:
A method is provided for the removal of lead contaminants from ores and mineral concentrates, comprising leaching the concentrates, at elevated temperatures, with an aqueous solution containing an aminopolycarboxylic acid. After separating the solution from the concentrates, lead can be precipitated by treating the solution with a sulfide; the solution can be recycled for use as a leachant.
摘要:
Lead constituents may be removed from a dross to produce a copper matte low in lead assay by melting the dross at temperature in excess of 900.degree. C., allowing the molten dross to separate into a lead bullion layer and a matte layer, removing the lead bullion layer from the matte layer, then heating the matte layer to a temperature in excess of 1000.degree. C., and removing the lead sulphide therefrom as a fume.