Abstract: Systems, methods, and devices are disclosed for producing quantum particles (e.g., quantum dots) having a uniform size by vaporization of molten precursor droplets. More particularly, the present technology produces quantum dots by melting or liquefying solid and substantially pure precursor materials followed by production of uniformly sized droplets of molten precursor by use of a droplet maker into a microwave generated plasma torch.

Abstract: A microwave plasma apparatus for processing a material includes a plasma chamber, a microwave radiation source, and a waveguide guiding microwave radiation from the microwave radiation source to the plasma chamber. A process gas flows through the plasma chamber and the microwave radiation couples to the process gas to produce a plasma jet. A process material is introduced to the plasma chamber, becomes entrained in the plasma jet, and is thereby transformed to a stream of product material droplets or particles. The product material droplets or particles are substantially more uniform in size, velocity, temperature, and melt state than are droplets or particles produced by prior devices.

Abstract: Systems, methods, and devices are disclosed for producing substantially uniform droplets. The system includes a fluid reservoir vessel defining a fluid reservoir, a separation membrane at one end of the fluid reservoir, at least one capillary channel at an opposite end of the fluid reservoir, a solution dispenser, and a piezo actuator in contact with a separation membrane. The separation membrane has a thickness greater than about 0.2 mm, and the solution dispenser maintains the fluid reservoir filled with fluid such that the fluid simultaneously contacts the separation membrane and the capillary channel. The solution dispenser maintains the fluid reservoir under pressure to create a fluid stream exiting the capillary. The piezo actuator is in contact with the separation membrane on a side opposite that in contact with the fluid, and the piezo actuator transfers a pressure wave through the fluid in the fluid reservoir to break up the fluid stream into uniform droplets.

Abstract: Feed material comprising uniform solution precursor droplets is processed in a uniform melt state using microwave generated plasma. The plasma torch employed is capable of generating laminar gas flows and providing a uniform temperature profile within the plasma. Plasma exhaust products are quenched at high rates to yield amorphous products. Products of this process include spherical, highly porous and amorphous oxide ceramic particles such as magnesia-yttria (MgO—Y2O3). The present invention can also be used to produce amorphous non oxide ceramic particles comprised of Boron, Carbon, and Nitrogen which can be subsequently consolidated into super hard materials.

Abstract: There is disclosed a piezoelectric droplet maker that is driven at high frequency and energized with high power and high frequency Operational Amplifier (OP-AMP) electronics. The droplet maker implements a method of producing jets of uniform droplets of solution precursors (or any other homogeneous liquids). The formation of droplets results from stream break up due to the disturbance of liquid jets by the piezo actuator as they leave an orifice. This disturbance can be electronically tuned to produce uniform droplets with high repeatability. In another aspect, the droplet maker can be used to inject axially uniform diameter solution precursor droplets into process gas flow of a microwave plasma apparatus.

Abstract: A method for processing feed material to produce dense and spheroidal products is described. The feed material is comprised of powder particles from the spray-drying technique or solution precursor droplets from ceramic or metallic materials. The feed material is processed using plasma generated from a microwave. The microwave plasma torch employed is capable of generating laminar flow during processing which allows for the production of spheroidal particles with a homogenous materials distribution. This results in products having improved thermal properties, improved corrosion and wear resistance and a higher tolerance to interface stresses.

Abstract: Disclosed herein is a method to produce multiphase composite materials directly from solution precursor droplets by a fast pyrolysis process using a microwave plasma embodiment containing a microwave generating source, a dielectric plasma torch, and a droplet maker. Here, using homogenous solution precursors, droplets are generated with a narrow size distribution, and are injected and introduced into the microwave plasma torch with generally uniform thermal path. The generally uniform thermal path in the torch is achieved by axial injection of droplets into an axisymmetric hot zone with laminar flows. Upon exposing to high temperature within the plasma with controlled residence time, the droplets are pyrolyzed and converted into particles by quenching with a controlled rate of the exhaust gas in a gas chamber. The particles generated have generally uniform sizes and uniform thermal history, and can be used for a variety of applications.

Abstract: A method for processing feed material to produce dense and spheroidal products is described. The feed material is comprised of powder particles from the spray-drying technique or solution precursor droplets from ceramic or metallic materials. The feed material is processed using plasma generated from a microwave. The microwave plasma torch employed is capable of generating laminar flow during processing which allows for the production of spheroidal particles with a homogenous materials distribution. This results in products having improved thermal properties, improved corrosion and wear resistance and a higher tolerance to interface stresses.

Abstract: Feed material comprising uniform solution precursor droplets is processed in a uniform melt state using microwave generated plasma. The plasma torch employed is capable of generating laminar gas flows and providing a uniform temperature profile within the plasma. Plasma exhaust products are quenched at high rates to yield amorphous products. Products of this process include spherical, highly porous and amorphous oxide ceramic particles such as magnesia-yttria (MgO—Y2O3). The present invention can also be used to produce amorphous non oxide ceramic particles comprised of Boron, Carbon, and Nitrogen which can be subsequently consolidated into super hard materials.

Abstract: A method for processing feed material to produce dense and spheroidal products is described. The feed material is comprised of powder particles from the spray-drying technique or solution precursor droplets from ceramic or metallic materials. The feed material is processed using plasma generated from a microwave. The microwave plasma torch employed is capable of generating laminar flow during processing which allows for the production of spheroidal particles with a homogenous materials distribution. This results in products having improved thermal properties, improved corrosion and wear resistance and a higher tolerance to interface stresses.

Abstract: Feed material comprising uniform solution precursor droplets is processed in a uniform melt state using microwave generated plasma. The plasma torch employed is capable of generating laminar gas flows and providing a uniform temperature profile within the plasma. Plasma exhaust products are quenched at high rates to yield amorphous products. Products of this process include spherical, highly porous and amorphous oxide ceramic particles such as magnesia-yttria (MgO—Y2O3). The present invention can also be used to produce amorphous non oxide ceramic particles comprised of Boron, Carbon, and Nitrogen which can be subsequently consolidated into super hard materials.