375results about "Silicon carbide" patented technology

The present invention relates to a composite powder for use in a negative electrode of a battery, the composite powder comprising composite particles and carbon nanotubes, the composite particles comprising a carbonaceous matrix material in which silicon-based particles are embedded, and wherein the surfaces of the composite particles are at least partially covered by the carbon nanotubes.

Ultrafast flash evaporation joule heating synthesis methods and systems, more particularly, ultrafast synthesis methods for recovering metals from ores, fly ash, and bauxite residue (red mud).

The present application provides a kind of silicon-carbon negative electrode material and its preparation method.The silicon-carbon negative electrode material includes carbon skeleton with pore structure and silicon-based material arranged in the pore structure, in the region from the surface of the silicon-carbon negative electrode material to the inside extending 10nm from the surface, the content of high-valence silicon is less than 25% relative to the total amount of low-valence silicon and high-valence silicon, wherein the low-valence silicon is 0-valence to 2-valence silicon, and the high-valence silicon is 3-valence to 4-valence silicon.Thereby, the lithium extraction gram capacity and the first coulomb efficiency of the silicon-carbon negative electrode material can be improved, and the discharge gram capacity and the first coulomb efficiency of the secondary battery can be improved.

The invention discloses a double-layer nano silicon-based material as well as a preparation method and application thereof, and belongs to the technical field of energy storage. The double-layer nano silicon-based material sequentially comprises a core layer, a first shell layer and a second shell layer from inside to outside, the core layer is nano silicon, the first shell layer is a silicon carbide layer with the thickness of 1.1-5.0 nm, and the second shell layer is a carbon layer with the thickness of 1.1-4.2 nm; a carbon-silicon bond is formed between the core layer and the first shell layer, and a carbon-silicon bond is formed between the first shell layer and the second shell layer. On one hand, silicon volume expansion is physically limited through a high-strength rigid framework; on the other hand, an ion / electron synergistic conduction functional interface layer is constructed, and unification of stress buffering, interface stability and rapid dynamics is achieved.

The invention discloses a reaction device for cleaning the surface of a silicon carbide ring, and relates to the technical field of polycrystalline silicon production. Comprising a reaction assembly, the reaction assembly comprises a tank body and further comprises a lifting assembly, the lifting assembly comprises an annular block and a mounting plate, the annular block is rotatably arranged in the tank body, an annular gear is fixed below the annular block, the mounting plate is fixed in the tank body, and a plurality of threaded rods are rotatably arranged between the mounting plate and the bottom of the tank body; driven gears are fixed to the ends of the multiple threaded rods, a lifting motor is fixed to the bottom of the tank body, an output shaft of the lifting motor is connected with the threaded rods through couplings, a lifting circular plate is connected to the multiple threaded rods in a threaded mode, a placing assembly is arranged on the lifting circular plate, a circulating assembly is arranged in the tank body, and a plurality of rotating assemblies are arranged above the tank body; the contact area with the circular ring plate can be reduced, meanwhile, the rubber block can drive the silicon carbide ring to rotate, the contact part is prevented from being blocked, and the cleaning efficiency of the silicon carbide ring is improved.

The utility model provides a silicon carbide powder pickling device, which relates to the field of silicon carbide processing, and comprises a plurality of supporting legs, the outer surface of each supporting leg is fixedly connected with a first bracket, and the equipment comprises a transmission system consisting of a first motor, a transmission rod, a rotating disc, a rotating rod, a push-pull rod, a limiting bracket, a transmission arm and the like. Complex and accurate relative movement of the first bulkhead and the second bulkhead is achieved, compared with existing equipment, the transmission design can more effectively break the agglomeration phenomenon of powder in the acid pickling process, it is ensured that each powder can be fully exposed in acid liquor, the uniformity and thoroughness of acid pickling are greatly improved, and the production efficiency is improved. By means of the synergistic effect, the powder and the acid liquor can be more fully mixed within a shorter time, the pickling reaction process is accelerated, the pickling efficiency is remarkably improved, the powder can be promoted to rapidly pass through the screen through the motion modes of swinging, vibration and the like of the partition frame, and the period of the whole pickling technological process is greatly shortened.

A process for producing solar grade silicon from silica sand employs a plurality of plasma furnaces to perform a sequence of chemical reactions together with other process steps to produce solar grade silicon. The plasma furnace generates a stable dirty-air, donut-shaped plasma into which particulate matter can be introduced. The plasma in the first two stages is formed by gases from the chemical reactions and in the third from inert gasses. Cyclone separators are used to extract particulates from the plasma in an inert gas that prevents reverse reactions as the particulate cools.

The present invention belongs to the technical field of composite silicon-based negative electrode materials and discloses a composite silicon-based negative electrode material, a preparation method, and a solid-state battery. The composite silicon-based negative electrode material comprises a graphite substrate and silicon carbide nanowires and nanosilicon particles attached to the surface of the graphite substrate. The silicon carbide nanowires are interwoven to form a network structure, and the nanosilicon particles are dispersed in the network structure. The nanosilicon particles are dispersed in the network of interwoven silicon carbide nanowires, presenting a porous structure similar to that of reinforced concrete. The porous structure provides space for volume expansion, mitigating damage to the electrode structure caused by volume expansion during lithium insertion and extraction of the silicon-based negative electrode. At the same time, the one-dimensional silicon carbide therein, due to its high mechanical strength, can mitigate damage to the electrode structure caused by long-term cycling of the silicon negative electrode, thereby improving the mechanical properties of the silicon negative electrode and thus improving the cycling performance of the silicon electrode.

A method is disclosed comprising providing a carbonaceous substrate; performing a chemical vapor deposition process on the carbonaceous substrate using a mixture of precursor gasses comprising a silicon precursor gas comprising trichlorosilane, and a carbon precursor gas selected from carbon-carbon double bond hydrocarbons and carbon-carbon triple bond hydrocarbons; and via said chemical vapor deposition process, forming a polycrystalline cubic silicon carbide layer with crystallographic orientation.

The invention belongs to the technical field of preparation of high-temperature heat-insulating and electromagnetic wave-absorbing materials, and relates to a bamboo-like silicon carbide nanowire based on freeze-dried vegetables / fruits and a preparation method and application of the bamboo-like silicon carbide nanowire based on the freeze-dried vegetables / fruits, and the preparation method comprises the following steps: putting the vegetables / fruits in a freeze dryer to obtain the freeze-dried vegetables / fruits; putting the freeze-dried vegetables / fruits into a high-temperature tubular furnace for carbonization to obtain a carbon template; putting the carbon template and a silicon source into a graphite crucible, putting the graphite crucible into a high-temperature tubular furnace, and calcining to obtain the bamboo-like silicon carbide nanowire based on the freeze-dried vegetables / fruits. The bamboo-like silicon carbide nanowire prepared by the method has excellent high-temperature heat insulation property and remarkable broadband electromagnetic wave absorption property, so that the enhancement of double functions of heat insulation and wave absorption is synergistically realized on the basis of a single material. The preparation process is simple and stable in flow, good in repeatability, green in raw material and extremely low in cost, and the problems of collapse and atrophy of the material structure caused by high temperature are solved.

The embodiments disclosed herein relate to methods and systems for efficient Joule heating of powder materials, and in particular, Joule heating of a powder feedstock that is mixed while the powder is Joule heated. The methods and systems apply to powder materials comprising carbon, silicon-material powders, and plastic powders. The Joule heating of this invention can control the degree of carbon graphitization, the degree of silicon-material crystallization, and the carbonization of plastics and polymers.

The invention concerns the field of noble metal processing and relates to a platinoid-silicide- and silicon-carbide-containing mixture, which is recycled from platinoide- and SiC-containing materials, enriched, concentrated and / or cleaned, and to a method for producing same. The problem addressed by the present invention consists in specifying a platinoid-silicide- and silicon-carbide-containing mixture in which the platinoid-silicides are present at high yield and / or high purity and which is produced from platinoid- and SiC-containing materials by way of a simple and cost-effective method. The problem is solved by a platinoid-silicide- and silicon-carbide-containing mixture in which platinoids are present at a concentration of at least 1 mass % and in which, in addition to silicon carbide particles and silicon carbide particle agglomorates, the platinoids are present as platinoid silicide particles and / or as agglomerates of platinoid silicide particles, and or platinoid silicide particles bond the silicon carbide particles into an agglomerate and / or are arranged on the surface of the silicon carbide particles, wherein the silicon carbide of the silicon carbide particles is present as technically pure silicon carbide.

The invention provides a deep carbon removal method for silicon carbide powder based on plasma-assisted composite catalytic oxidation, which is characterized by comprising the following steps: S1, cleaning and drying silicon carbide powder raw materials with acid to obtain pretreated silicon carbide powder; s2, immersing the pretreated silicon carbide powder into a cobalt nitrate, manganese nitrate or ferric nitrate solution, and carrying out dispersion treatment, evaporation treatment and calcination treatment to obtain a metal oxide / silicon carbide composite catalyst; s3, placing the metal oxide / silicon carbide composite catalyst in a radio frequency plasma reactor, and carrying out an oxidation reaction; and S4, after the oxidation reaction is finished, carrying out post-treatment to obtain the carbon-removed silicon carbide powder. The carbon removal effect is obviously better than that of a traditional high-temperature oxidation method.

A negative electrode active material for a lithium secondary battery, according an embodiment of the present invention, comprises a silicon carbon (Si / C) composite having a modulus value (A) of 15-25 GPa and a hardness value (B) of 2500-5000 MPa.

The present invention relates to a composite powder for use in a battery anode, the composite powder comprising composite particles comprising a carbonaceous matrix material having silicon-based particles embedded therein and carbon nanotubes, the surfaces of the composite particles being at least partially covered by the carbon nanotubes.

The invention provides a mineral treatment system and a mineral treatment method.The mineral treatment system comprises a heating device and an electric heating assembly, the heating device comprises a heating part and an electric heating assembly, the heating part comprises a containing cavity used for containing a blocky structure containing SiO2, MgO and C, the electric heating assembly heats the blocky structure containing SiO2, MgO and C in a resistance heating mode, and the heating part is used for heating the blocky structure containing SiO2, MgO and C; carrying out a reaction until the real-time temperature of the blocky structure is greater than a first preset temperature to form SiC, gaseous Mg and gaseous CO; and the cooling part is provided with a cooling cavity, and the cooling cavity communicates with the containing cavity, so that gaseous Mg and CO in the containing cavity enter the cooling cavity to be cooled, and gaseous CO and solid Mg are formed. The problem that in the prior art, the added value of silicon dioxide and magnesium compounds obtained by treating serpentine through a wet treatment process is low is solved.

The invention relates to the technical field of silicon carbide, and discloses a method for removing a tungsten element in a silicon carbide raw material and silicon carbide powder. The method for removing the tungsten element in the silicon carbide raw material comprises the following steps: preparing a leaching agent; mixing a silicon carbide raw material and the leaching agent, and performing leaching reaction to obtain a solid-liquid mixture; carrying out post-treatment on the solid-liquid mixture to obtain silicon carbide powder; wherein the leaching agent comprises a strong oxidant and organic acid. According to the method, selective dissolution of tungsten impurities can be achieved under the mild condition, pollution to the environment is avoided, the requirements for environmental protection and industrial production are met, and the cost is greatly reduced.

An electromagnetic wave absorbing sheet that uses silicon carbide powder to impart light weight and high insulation properties and that can obtain an excellent noise attenuation effect in the submillimeter to millimeter wave bands is provided. The electromagnetic wave absorbing sheet of the present disclosure includes a substrate made of organic matter and a powder that is supported in the substrate and has silicon carbide (SiC) as a principal constituent. In X-ray diffraction using Cu-Kα as a radiation source on a surface of the electromagnetic wave absorbing sheet, a value I4H / I6H obtained by dividing a peak intensity I4H derived from 4H-SiC appearing at 20 = 34.4° to 35° by a peak intensity I6H derived from 6H-SiC appearing at 20 = 35° to 36° is a predetermined value or more.

The application discloses a high-crystalline semiconductor silicon carbide powder and a preparation method thereof. High-purity silicon carbide single crystal is cracked or broken, and silicon carbide powder with a particle size of 10-200 microns is screened out and mixed with high-purity carbon powder. The mixed carbon powder and silicon powder are placed at the bottom of a graphite crucible, and the mixed silicon carbide powder and high-purity carbon powder are placed at the upper part. A graphite cover is installed to seal the graphite crucible, and the graphite crucible is placed in a high-temperature sintering furnace. The furnace chamber is closed and vacuumized. The temperature is raised to 1050-1350 DEG C, and the temperature is kept for 1-15 hours. High-purity argon is introduced into the chamber until the pressure in the chamber reaches 10000-80000 Pa. The temperature is continuously raised to 1750-2000 DEG C, and the temperature is kept for 8-15 hours to synthesize the bottom silicon carbide powder. The temperature is continuously raised to 2000-2500 DEG C, and the pressure in the chamber is reduced to 1000-10000 Pa. High-purity argon is continuously introduced at a flow rate of 5-800 sccm, and the temperature is kept for 30-80 hours. The argon introduction is stopped, and the graphite crucible is cooled to room temperature to obtain the high-crystalline semiconductor silicon carbide powder. The high-crystalline semiconductor silicon carbide powder can be applied to the preparation of the third-generation semiconductor material silicon carbide single crystal material with high performance, low defects and low inclusion density.

The present application relates to graphene material and its preparation technology, specifically to a method for growing graphene on the surface of non-metallic particles on a large scale, which is suitable for large-scale preparation of graphene-coated non-metallic powder material. The present application uses a two-step method to grow graphene uniformly on the surface of a large number of non-metallic particles: first, mix a large number of non-metallic particles with a carbon source, and form a bulk composite material of non-metallic particles and carbon through low-temperature carbonization; then, pass current to the above bulk composite material using electrodes to heat it to a higher temperature, convert the carbon into graphene, until graphene-coated non-metallic particles are obtained, which are separated from each other, and the high-temperature heating process stops spontaneously. The present application can grow a graphene layer on the surface of a large number of non-metallic particles, the method is easy to scale up, and has the characteristics of good uniformity of graphene coating and high particle separation degree; at the same time, by taking advantage of the large resistance of graphene-coated non-metallic particles which are separated from each other, the high-temperature heating process stops spontaneously.

To provide a method and a system for obtaining a high-quality cubic silicon carbide.SOLUTION: A method (200) is disclosed. The method (200) includes: a step (205) of supplying a carbon-based substrate (S); a step (210) of performing a chemical vapor deposition process on the carbon-based substrate using a mixture of precursor gases, the mixture including a silicon precursor gas including trichlorosilane and a carbon precursor gas selected from a carbon-carbon double bond hydrocarbon and a carbon-carbon triple bond hydrocarbon; and a step (215) of forming a polycrystalline cubic silicon carbide layer having a {111} orientation through the chemical vapor deposition process.SELECTED DRAWING: Figure 1

The invention discloses a siliconized silicon carbide porous material block and a preparation method and application thereof, the siliconized silicon carbide porous material block comprises an intermediate and a silicon carbide layer coating the surface of the intermediate, the intermediate comprises a porous silicon carbide block and silicon crystals located in the pores, and the mass ratio of the silicon carbide block to the silicon crystals is (70-95): (5-30). According to the method, a siliconized silicon carbide porous material block and conventional silicon carbide powder are mixed in proportion, then the mixture is used for crystal growth, a silicon carbide layer outside the siliconized silicon carbide block begins to decompose preferentially along with decomposition of the initial mixture, and silicon inside the porous material begins to decompose along with decomposition of silicon carbide after the middle and later growth periods, so that the silicon carbide is formed. The carbon-silicon ratio in the middle-later period atmosphere is kept stable, and the quality of the silicon carbide crystal with relatively high thickness is improved.

The invention relates to a method for preparing high-purity porous silicon carbide ceramic from a biomass aerogel precursor. The method comprises the following specific steps: (1) preparing precursor sol; (2) gelatinizing, aging and forming a three-dimensional network structure; (3) solvent replacement; (4) performing supercritical drying to obtain biomass carbon-silicon dioxide composite aerogel; (5) carrying out carbon thermal reduction reaction to generate porous silicon carbide ceramic; and (6) decarbonizing and purifying to obtain the high-purity porous silicon carbide ceramic. The prepared porous silicon carbide ceramic material has high specific surface area, uniform pore size distribution and good mechanical strength, can effectively filter impurities such as particulate matters and harmful gases in gas, and shows excellent gas filtering performance. The material can be used in the fields of air purification, industrial waste gas treatment and the like, and has a wide application prospect.

Silicon carbide as a radioactive isotope energy source material, containing a single crystalline phase of a silicon carbide semiconductor structure in the form of a film, having n-type or p-type electrical conductivity for separating electron-hole pairs, comprising the elements: carbon isotope C 12 and additionally carbon isotope C 14 for converting its radiation energy into electrical energy, characterized in that the concentration of radioactive isotope C 14 in one of the n-type or p-type conductivity layers is from 5·10 17 to 10 20 cm ‑3 -3 14 , wherein the n-type or p-type conductivity silicon carbide layer is formed on the surface of a monocrystalline silicon substrate, the n-type or p-type conductivity silicon carbide layer with C 14 has a porous surface topography.

The application provides a ferroelectric metal and a preparation method and application thereof. The ferroelectric metal of the application is composed of cubic silicon carbide crystals and doping elements doped therein, wherein the concentration of the doping elements is greater than or equal to 1*10 18 cm ‑3 The material of the application can be prepared by a chemical vapor deposition method, a high-temperature solution growth method, a solid-phase sintering method, a pulse laser deposition method and the like. Since the conductivity of metal, the switching characteristics of ferroelectric and the force-electric coupling characteristics of piezoelectric are integrated, the ferroelectric metal of the application has great application value in the fields of high-performance transducers, high-sensitivity sensors, low-power micro-electro-mechanical system (MEMS), next-generation multifunctional electronic devices and the like.

The utility model relates to the technical field of sandstone desulfurization, and discloses a silicon carbide sand-making desulfurization device which comprises a desulfurization box, a feeding pipe is fixedly connected to the outer side of the desulfurization box, supporting rods are fixedly connected to the two sides of the exterior of the desulfurization box, and supporting blocks are fixedly connected to the tops of the supporting rods. An electric sliding rail is fixedly mounted at the top of the supporting block, a moving block is fixedly connected to the output end of the electric sliding rail, an air cylinder is fixedly mounted at the top of the moving block, a push rod is fixedly connected to the output end of the air cylinder, and a clamping block is fixedly connected to the bottom end of the push rod. The device has the following advantages and effects that sand grains are in contact with a desulfurizing agent in the desulfurizing box, so that the purpose of desulfurizing the sand grains can be achieved, the desulfurizing effect is good, and after desulfurization is completed, the sand net is moved to the outside of the desulfurizing box through the air cylinder and the electric sliding rail, so that the effect of conveniently taking out the sand net and the sand grains is achieved.

The utility model relates to the technical field of acid washing, and discloses acid washing equipment for silicon carbide micro powder, which comprises a cart, universal wheels are fixedly connected to the bottom of the cart, two tank bodies are fixedly connected to the top of the cart, feeding holes are formed in the tops of the two tank bodies, and the feeding holes are communicated with the cart. Material covers are fixedly connected to the tops of the two tank bodies, a plurality of supporting legs are arranged on the top of the cart, a protection assembly is arranged on the top of the feeding port, stirring assemblies are arranged in the tank bodies, a circulation assembly is arranged on the top of the cart, and a disassembly assembly is arranged in the tank bodies. According to the silicon carbide micro-powder cleaning device, by pushing the limiting column, the reset spring on the outer wall of the limiting column is driven to be compressed downwards, then the fixed circular ring is driven to move, and then the conical block is driven to move, so that the valve port is opened to enable liquid to pass through, reliable sealing can be formed, and cleaned silicon carbide micro-powder is prevented from reversely flowing back to an uncleaned area.

Disclosed are pellicles for use in extreme ultraviolet (EUV) lithography, the pellicles comprising silicon carbide nanostructures, and exhibiting high transmittance of EUV exposure light and high mechanical strength, as well as methods of using these pellicles.

The utility model relates to the technical field of green silicon carbide micro powder, in particular to green silicon carbide micro powder pickling and deacidification integrated equipment which comprises an acid washing device and a deacidification structure, the lower end of a first shell in the acid washing device is connected with an annular filter screen through a bolt, and the upper end of the annular filter screen is connected with a conical flow guide structure through a bolt. One side of a guide-in shell in the acid washing device is connected with a third shell in the acid removal structure through a second pipeline, the lower end of the third shell in the acid removal structure is connected with a third pipeline through a bolt, and the lower end of the third pipeline is connected with a fourth pipeline through a bolt; through a third pipeline and a fourth pipeline, the green silicon carbide micro powder can be conveyed into the first shell again, so that the green silicon carbide micro powder can be further deacidified, through a second electromagnetic valve, the green silicon carbide micro powder can be limited, and through a water inlet, residual acid can be diluted; the four sides of the third shell can be supported through the supporting plates and the supporting columns.

A silicon-carbon negative electrode material includes a carbon skeleton having a pore structure and a silicon-based material arranged in the pore structure, where in a region formed by extending from a surface of the silicon-carbon negative electrode material inward by 10 nm away from the surface, a content of high-valence silicon is less than 25% relative to a total amount of low-valence silicon and the high-valence silicon, where the low-valence silicon is silicon with a valence of 0 to 2, and the high-valence silicon is silicon with a valence of 3 to 4.