Patent classifications
C01B21/0641
METHOD AND APPARATUS FOR PREPARING BORON NITRIDE NANOTUBES BY HEAT TREATING BORON PRECURSOR PREPARED BY USING AIR-JET
A method and apparatus for preparing boron nitride nanotubes (BNNTs) according to an embodiment may ensure mass-production, may increase yield by reducing a production time, and may prepare BNNTs with high purity.
Boron nitride nanotube synthesis via direct induction
High quality, catalyst-free boron nitride nanotubes (BNNTs) that are long, flexible, have few wall molecules and few defects in the crystalline structure, can be efficiently produced by a process driven primarily by Direct Induction. Secondary Direct Induction coils, Direct Current heaters, lasers, and electric arcs can provide additional heating to tailor the processes and enhance the quality of the BN-NTs while reducing impurities. Heating the initial boron feed stock to temperatures causing it to act as an electrical conductor can be achieved by including refractory metals in the initial boron feed stock, or providing additional heat via lasers or electric arcs. Direct Induction processes may be energy efficient and sustainable for indefinite periods of time. Careful heat and gas flow profile management may be used to enhance production of high quality BNNT at significant production rates.
Method and apparatus for preparing boron nitride nanotubes by heat treating boron precursor prepared by using air-jet
A method and apparatus for preparing boron nitride nanotubes (BNNTs) according to an embodiment may ensure mass-production, may increase yield by reducing a production time, and may prepare BNNTs with high purity. The method includes steps of providing a first powder including boron, forming a second powder including a boron precursor by nano-sizing the first powder, forming a precursor disk by mixing the second powder with a binder; and growing BNNTs on the precursor disk.
TARGET HOLDERS, MULTIPLE-INCIDENCE ANGLE, AND MULTIZONE HEATING FOR BNNT SYNTHESIS
In the synthesis of boron nitride nanotubes (BNNTs) via high temperature, high pressure methods, a boron feedstock may be elevated above its melting point in a nitrogen environment at an elevated pressure. Methods and apparatus for supporting the boron feedstock and subsequent boron melt are described that enhance BNNT synthesis. A target holder having a boron nitride interface layer thermally insulates the target holder from the boron melt. Using one or more lasers as a heat source, mirrors may be positioned to reflect and control the distribution of heat in the chamber. The flow of nitrogen gas in the chamber may be heated and controlled through heating elements and flow control baffles to enhance BNNT formation. Cooling systems and baffle elements may provide additional control of the BNNT production process.
METAL NITRIDES AND/OR METAL CARBIDES WITH NANOCRYSTALLINE GRAIN STRUCTURE
Disclosed is a composition having nanoparticles or particles of a refractory metal, a refractory metal hydride, a refractory metal carbide, a refractory metal nitride, or a refractory metal boride, an organic compound consisting of carbon and hydrogen, and a nitrogenous compound consisting of carbon, nitrogen, and hydrogen. The composition, optionally containing the nitrogenous compound, is milled, cured to form a thermoset, compacted into a geometric shape, and heated in a nitrogen atmosphere at a temperature that forms a nanoparticle composition comprising nanoparticles of metal nitride and optionally metal carbide. The nanoparticles have a uniform distribution of the nitride or carbide.
Induction-coupled plasma synthesis of boron nitrade nanotubes
Described herein are processes and apparatus for the large-scale synthesis of boron nitride nanotubes (BNNTs) by induction-coupled plasma (ICP). A boron-containing feedstock may be heated by ICP in the presence of nitrogen gas at an elevated pressure, to form vaporized boron. The vaporized boron may be cooled to form boron droplets, such as nanodroplets. Cooling may take place using a condenser, for example. BNNTs may then form downstream and can be harvested.
System and methods for fabricating boron nitride nanostructures
This disclosure provides systems, methods, and apparatus related to boron nitride nanomaterials. In one aspect, a method includes generating a directed flow of plasma. A boron-containing species is introduced to the directed flow of the plasma. Boron nitride nanostructures are formed in a chamber. In another aspect, a method includes generating a directed flow of plasma using nitrogen gas. A boron-containing species is introduced to the directed flow of the plasma. The boron-containing species can consist of boron powder, boron nitride powder, and/or boron oxide powder. Boron nitride nanostructures are formed in a chamber, with a pressure in the chamber being about 3 atmospheres or greater.
Target holders, multiple-incidence angle, and multizone heating for BNNT synthesis
In the synthesis of boron nitride nanotubes (BNNTs) via high temperature, high pressure methods, a boron feedstock may be elevated above its melting point in a nitrogen environment at an elevated pressure. Methods and apparatus for supporting the boron feedstock and subsequent boron melt are described that enhance BNNT synthesis. A target holder having a boron nitride interface layer thermally insulates the target holder from the boron melt. Using one or more lasers as a heat source, mirrors may be positioned to reflect and control the distribution of heat in the chamber. The flow of nitrogen gas in the chamber may be heated and controlled through heating elements and flow control baffles to enhance BNNT formation. Cooling systems and baffle elements may provide additional control of the BNNT production process.
Boron Nitride Nanomaterial, and Preparation Method and Use Thereof
The present disclosure discloses a boron nitride nanomaterial, and preparation method and use thereof. The preparation method comprises: heating a precursor in a nitrogen atmosphere to a high temperature, to prepare the boron nitride nanomaterial. The precursor comprises boron, and at least one metal element, and/or at least one non-metallic element rather than boron, the metal element is at least one selected from the group consisting of lithium, beryllium, magnesium, calcium, strontium, barium, aluminum, gallium, indium, zinc, and titanium, and the non-metallic element comprises silicon. The preparation method of the boron nitride nanomaterial provided by the disclosure is simple, controllable, and economical with readily available and inexpensive starting materials, and high conversion rates of the starting materials, and facilitates mass production. Furthermore, the obtained boron nitride nanomaterials further have advantages, such as excellent quality, and controllable appearance, and have very good application prospects in many fields, such as electronic devices, deep ultraviolet light emitting, composite materials, heat dissipating materials, friction materials, drug loading, and catalyst loading.
CONTINUOUS BORON NITRIDE NANOTUBE FIBERS
Described herein are apparatus, systems, and methods for the continuous production of BNNT fibers, BNNT strands and BNNT initial yarns having few defects and good alignment. BNNTs may be formed by thermally exciting a boron feedstock in a chamber in the presence of pressurized nitrogen. BNNTs are encouraged to self-assemble into aligned BNNT fibers in a growth zone, and form BNNT strands and BNNT initial yarns, through various combinations of nitrogen gas flow direction and velocities, heat source distribution, temperature gradients, and chamber geometries.