46 results about "Carbon impurities" patented technology

The application discloses a treatment method for reducing carbon content of REBCO powder, and relates to the technical field of superconducting material preparation. The treatment method is that the REBCO powder is placed in an ozone-containing atmosphere for heat treatment. The core principle of the treatment method is that the strong oxidizing property of ozone and active oxygen atoms generated by the decomposition of ozone are used to directly oxidize carbon impurities in the REBCO powder into CO2 gas at a lower temperature, and meanwhile, the superconducting phase is avoided from being damaged. It is verified by a carbon analyzer that the carbon reduction efficiency of the powder after ozone heat treatment is several times higher than that of the powder after traditional oxygen atmosphere treatment.

This application relates to the field of electrolyte materials technology, and in particular to a method for preparing lithium selenide. The method includes: obtaining a precursor source, the precursor source including lithium nitride and a selenium source, and subjecting the precursor source to multiple calcination treatments to obtain lithium selenide. The present invention uses lithium nitride as a lithium source and a selenium source to undergo a redox reaction to generate lithium selenide and nitrogen gas. This method has a low cost, does not produce carbon impurities in the prepared product, and the prepared lithium selenide can be used directly as a high-purity raw material for solid electrolytes. In addition, the reaction between lithium nitride and selenium has low exothermic reaction, the reaction is easy to control, and the safety is higher, avoiding the problem of low safety caused by high exothermic reaction of elemental selenium and elemental lithium in the prior art.

The invention provides a regeneration method of a decommissioned lithium iron phosphate positive electrode material, which comprises the following steps: uniformly mixing the decommissioned lithium iron phosphate positive electrode material and a lithium salt supplement in an organic solvent to obtain a precursor mixture; and carrying out a repair reaction on the precursor mixture in a high-pressure CO2 atmosphere to obtain the regenerated lithium iron phosphate material. According to the method, carbon impurities, especially inorganic carbon, are removed through pressurized CO2 assisted heat treatment, meanwhile, structural defects are repaired, active sites are exposed through selective carbon removal, lithium migration is promoted, residual carbon maintains a conductive network, and in addition, agglomeration of a high-voltage inhibiting material guarantees structural uniformity; therefore, compared with a traditional method, the regenerated lithium iron phosphate material is lower in lithium / iron antisite defect rate and more stable in structure, meanwhile, stable components of the regenerated lithium iron phosphate material are ensured, and the electrochemical performance is guaranteed.

The invention relates to the technical field of metallurgical engineering, and provides a method for determining organic carbon impurities in titanium tetrachloride, which comprises the following steps: filtering a titanium tetrachloride sample to remove inorganic carbon impurities; reacting the filtered sample with an oxidizing agent under pressurizing and heating conditions, so that organic carbon impurities in the sample are converted into a carbon-containing gas-phase product and solid-phase residues; collecting and measuring the carbon content in the carbon-containing gas-phase product to obtain the gas-phase carbon content; carrying out distillation separation on the reacted liquid, collecting residues, and measuring the carbon content in the residues to obtain the solid-phase carbon content; and adding the gas-phase carbon content and the solid-phase carbon content to obtain the content of the organic carbon impurity in the titanium tetrachloride. According to the scheme, high-precision and high-specificity quantitative analysis on the organic carbon impurities in the titanium tetrachloride is realized.

The invention relates to small-particle-size molybdenum powder and a preparation method thereof, and belongs to the field of powder metallurgy preparation.The preparation method comprises the steps that a molybdenum source, nanometer conductive carbon black and a dispersing agent are mixed in an aqueous solvent, and a composite precursor with the nanometer conductive carbon black isolated and dispersed by the molybdenum source is constructed through spray drying; then carrying out two-step treatment of low-temperature carbon thermal reduction and medium-temperature carbon migration in an inert atmosphere to obtain a pre-reduced intermediate product; and finally, deep reduction and gas-phase decarburization are completed in a wet hydrogen atmosphere with specific water vapor content, and residual carbon is thoroughly removed through water gas reaction. According to the method, the core contradiction that the granularity refinement of the molybdenum powder and the deep removal of the carbon impurities are difficult to consider in the traditional method is solved through the coordinated regulation of the whole process from the precursor structure design to the reduction decarburization process, and the method has the advantages of superfine granularity, extremely low carbon and oxygen impurity content and excellent comprehensive performance.

The application provides a method for removing carbon impurities and metal impurities from a single-walled carbon nanotube crude product, and relates to the technical field of separation and purification of carbon nanotube materials. The method comprises the following steps: performing calcination treatment on the single-walled carbon nanotube under a carbon dioxide atmosphere, then performing toluene reflux, adding polyvinylpyrrolidone and acid, and obtaining purified single-walled carbon nanotubes. The method removes excess amorphous carbon by calcination under the condition of carbon dioxide gas, realizes high separation of the single-walled carbon nanotubes by refluxing in toluene, simultaneously adds concentrated acid and polyvinylpyrrolidone to remove metal impurities, and finally performs high-temperature calcination to decompose the residual polyvinylpyrrolidone, thereby improving the purity of the single-walled carbon nanotubes. The purification method has the characteristics of high purity, high efficiency and high-quality products. The method has relatively excellent purification efficiency, and the purified single-walled carbon nanotubes have relatively high purity.

The invention discloses a device and a method for removing organic carbon in hydrogen peroxide. The device comprises a hydrogen peroxide receiving device for receiving hydrogen peroxide to be treated; the resin adsorption device is connected with the hydrogen peroxide adsorption device, and resin in the resin adsorption device can perform adsorption treatment on organic carbon in the hydrogen peroxide; the treated qualified hydrogen peroxide flows into a qualified hydrogen peroxide liquid receiving device to be collected. In addition, a resin regeneration device connected with the resin adsorption device is further arranged, and when resin is regenerated, the device can provide resin regeneration treatment for the resin adsorption device. The resin regeneration device is composed of a resin regeneration tower, a solution A storage device, a solution B storage device and a nitrogen storage device. Through reasonable arrangement and cooperative work of all the devices, the technical problems that in the prior art, the removal efficiency of organic carbon impurities in hydrogen peroxide is low, the regeneration process is tedious, and safety is poor are effectively solved.

The application discloses a kind of MOCVD preparation method and device of wafer level single crystal molybdenum disulfide;The preparation method uses six carbonyl molybdenum Mo (CO) 6 and liquid carbon disulfide CS2 as molybdenum source and sulfur source respectively, different from traditional MOCVD growth process, precursor used in the application does not contain hydrogen element, avoid the side effect caused by hydrogen element, and increase the pre-reaction of source cracking, by introducing oxygen, generate intermediate product molybdenum trioxide (MoO3) and sulfur element (S) in pre-reaction chamber, to the reaction chamber on the substrate surface deposition, effectively avoid the introduction of carbon impurities, realize the nucleation and epitaxial growth of single crystal orientation on the substrate surface, obtain high uniformity and continuity single crystal molybdenum disulfide film, realize 6 inch and above size single crystal wafer scale preparation, meet the key needs of high density, high performance electronic device integration.

This invention provides a method and apparatus for segmented and precisely controlled enhanced separation of carbon- and arsenic-containing fine-grained gold ore, belonging to the field of mineral processing technology. The apparatus includes a feeding system, a heating system, a suspension roasting furnace, a gas supply system, a detection system, and a grinding and leaching system. The method involves: first, crushing and grinding the carbon- and arsenic-containing fine-grained gold ore, then drying it; next, conveying the ore powder to the pre-oxidation chamber of the suspension roasting furnace for pre-oxidation and arsenic removal roasting in a suspended state; then feeding it into the oxidation chamber of the suspension roasting furnace for decarburization roasting in a suspended state; after the decarburized roasted ore has naturally cooled, adding water for grinding, and cyaniding the slurry to obtain a gold-bearing precious liquor. This invention can precisely control the desulfurization and decarburization of carbon- and arsenic-containing fine-grained gold ore under suitable conditions, achieving high mass and heat transfer efficiency, high arsenic and carbon impurity removal rates, low energy consumption and cost per unit processing volume, easily controllable and stable product properties, and easy scaling up of equipment.

The present application relates to a kind of small granularity molybdenum powder and its preparation method, belong to powder metallurgy preparation field, molybdenum source, nano conductive carbon black and dispersant are mixed in aqueous solvent, and the composite precursor of nano conductive carbon black is isolated and dispersed by molybdenum source is constructed by spray drying;Subsequently, two-step processing of low-temperature carbon thermal reduction and medium-temperature carbon migration is carried out in inert atmosphere, and pre-reduction intermediate product is obtained;Finally, deep reduction and gas phase decarburization are completed in the wet hydrogen atmosphere of specific water vapor content, and residual carbon is completely removed using water gas reaction.The present application solves the core contradiction that molybdenum powder granularity refinement and carbon impurity deep removal are difficult to consider in traditional method by whole-process synergistic regulation from precursor structure design to reduction decarburization process, with ultrafine granularity, extremely low carbon and oxygen impurity content, and excellent comprehensive performance.

The invention provides a composite carbon material based on coal gasification slag and a preparation method and application thereof.The preparation method comprises the steps that the coal gasification slag with the water content ranging from 16 wt% to 30 wt% is loaded into an electromagnetic induction container, electromagnetic induction heating treatment is conducted through alternating current, the composite carbon material is output after heating is conducted to the temperature ranging from 1200 DEG C to 2500 DEG C, the frequency of the alternating current ranges from 12000 Hz to 15000 Hz, and the electromagnetic induction heating treatment is conducted on the coal gasification slag with the water content ranging from 16 wt% to 30 wt%; and the output power of the power supply is 15000W to 20000W. The coal gasification slag belongs to industrial byproduct waste, selective enrichment of a carbon structure and effective removal of non-carbon impurities can be realized under the action of a high-temperature electromagnetic field by introducing an electromagnetic induction heating process, and the crystallinity, orderliness and purity of a carbon phase in a material are remarkably improved; the composite carbon material with high specific surface area, an sp2 / sp3 hybrid structure and a multi-element synergistic stabilization mechanism is formed, the composite carbon material is named as Ordos alkene, and the Ordos alkene shows good conductivity, light absorption and high-temperature stability and is suitable for multiple fields of photoelectric functional materials, microwave absorption materials, energy storage device electrodes and the like.

The invention provides chelate resin, a preparation method of the chelate resin and application of the chelate resin to purification of regenerated gas of a polycrystalline silicon adsorption tower. The preparation method comprises the following steps: preparation of crosslinked polystyrene microspheres, chloromethylation of polystyrene-divinyl benzene microspheres and grafting of activated stilbene glucoside. The chelating resin and the molecular sieve are matched for use, so that impurities such as B, P and methane in regenerated hydrogen of an adsorption tower in a polycrystalline silicon production technology can be efficiently removed, the accumulation amount of boron, phosphorus and carbon impurities in a large polycrystalline silicon production system along with time change is reduced, and the quality of polycrystalline silicon can be greatly improved.

The application discloses an easily-dispersed high-conductivity high-purity single-wall carbon nanotube material and a preparation method thereof, relates to the technical field of single-wall carbon nanotube material preparation, and comprises the following steps: mixing single-wall carbon nanotube crude pipes with a nitrogen source, performing a reaction in a tube furnace to obtain carbon pipe intermediate product 1; mixing the carbon pipe intermediate product 1 with a dispersing agent, then mixing the carbon pipe intermediate product 1 with a solvent, performing emulsification, and performing suction filtration to obtain carbon pipe intermediate product 2; mixing the carbon pipe intermediate product 2 with mixed acid to perform a reaction, and performing cleaning and drying to obtain a final product. The single-wall carbon nanotube crude pipes are mixed with a nitrogen-containing nonmetal compound nitrogen source, compressed air is introduced to perform a reaction, and then dispersion and mixed acid treatment are sequentially performed, so that the effect of effectively removing amorphous carbon impurities and metal catalyst impurities is achieved, and the problem that, due to insufficient purity of existing carbon pipes, when the carbon pipes are used as conductive additives to prepare electrode materials, the uniformity of an electrode conductive network cannot be guaranteed, and then the overall electrochemical performance of the electrode is affected can be solved.

The invention relates to the technical field of carbon nanotube impurity removal, in particular to a purification method of a single-walled carbon nanotube, the high-purity single-walled carbon nanotube and application of the high-purity single-walled carbon nanotube. The invention provides a high-purity single-walled carbon nanotube. The high-purity single-walled carbon nanotube is characterized in that in mixed acid prepared from perchloric acid, concentrated sulfuric acid and concentrated nitric acid according to the volume ratio of 1: 3: 3, the mass content of metal measured in a test that the mass ratio of the high-purity single-walled carbon nanotube to the mixed acid is 1: 100 and the temperature is 200 DEG C for 30 min is smaller than or equal to 0.5%; the rapid oxidation weight loss temperature in a thermogravimetric differential curve obtained by testing the high-purity single-walled carbon nanotube in an air atmosphere under the condition that the heating rate is 10 DEG C / min is 740-800 DEG C. The high-purity single-walled carbon nanotube has relatively low metal impurities and carbon impurities, high conductivity and good conductivity, and is beneficial to improving the electrochemical performance of a battery prepared from the high-purity single-walled carbon nanotube.

The invention relates to a method for producing lithium sulfide with reduced or no carbon impurities, in which lithium sulfate and optionally lithium sulfite, lithium disulfate and / or other lithium sulfur oxides, as well as the carbon impurities containing lithium sulfide, are treated with hydrogen gas at a temperature in the range of 300 to 600 DEG C. The invention also relates to a lithium sulfide which can be produced in this way and which has a carbon impurity content of less than 2.0% by weight, based on the weight of the lithium sulfide. The lithium sulfide is used to produce battery components, preferably solid electrolytes, and solid state batteries.

The invention provides a method for preparing ultra-fine tungsten powder with ultra-low carbon content based on carbon thermal reduction of tungsten oxide, which comprises the following steps: 1) by using tungsten oxide as a tungsten source, carrying out ball milling and refining on the tungsten oxide to enable the particle size D50 of the tungsten oxide to be less than 1 mu m; 2) uniformly mixing the ball-milled tungsten oxide with nano carbon black with the particle size of 100-200 nm, and carrying out carbon thermal pre-reduction at 950-1050 DEG C in an inert atmosphere under the carbon-deficient condition that the molar ratio of the carbon black to the tungsten oxide is 1.0-1.7; and (3) the pre-reduced tungsten powder is placed in a wet hydrogen atmosphere with the dew point ranging from-20 DEG C to 20 DEG C, further treatment is conducted at the temperature ranging from 750 DEG C to 850 DEG C, deep decarburization is achieved, and residual oxygen is synchronously removed. The purity of the ultra-low-carbon-content superfine tungsten powder reaches 99.9% or above, the particle size distribution is smaller than 100 nm, the carbon content is smaller than 50 ppm, and the carbon impurity control level of the hydrogen reduction process is achieved in the carbon thermal reduction process.

The invention relates to a synthesis device for mass production of SiC powder by optimizing a high-temperature area position and a SiC powder production method.According to the synthesis device, a graphite structure is additionally arranged at the bottom of a crucible barrel, a hollow cavity structure is arranged in a graphite base, the crucible barrel and the graphite base are coaxially arranged, and the central axes of the crucible barrel and the graphite base coincide; the heat preservation layer is arranged outside the crucible barrel, so that the position of a high-temperature area is improved, the radial temperature gradient is optimized, cracking of the bottom of the crucible and growth of SiC particles are effectively prevented, the axial temperature gradient is adjusted and controlled through process setting, the discharging ratio of large-particle-size SiC powder can be increased, and synthesis of high-purity, large-batch and low-carbon-impurity-content SiC powder is facilitated.

The invention discloses a carbon impurity source inhibition and oxygen-carbon content cooperative regulation and control method, and relates to the technical field of intelligent manufacturing, and the method comprises the following steps: S1, carrying out carbon impurity detection on a reaction raw material, carrying out physical purification and chemical modification treatment according to a detection result, constructing an anti-oxidation carbon barrier layer on the surface of the raw material, and completing raw material pretreatment; and S2, based on the pretreated raw materials, feeding the pretreated raw materials into a reaction device, constructing an adjustable mixed atmosphere, and collecting real-time data of carbon impurities and oxygen content in a reaction system. According to the carbon impurity source inhibition and oxygen-carbon content collaborative regulation and control method provided by the invention, a full-chain intelligent regulation and control system is constructed, carbon impurity inhibition and oxygen-carbon content collaborative optimization are realized from the source to the tail end, and the method has a remarkable practical value and has the core benefits that the limitation of traditional tail end treatment and independent regulation and control is broken through; the risk of performance fluctuation is reduced, and the core performance index of the product is improved.

The invention discloses a method for reducing the content of carbon impurities in high-pressure tantalum powder. The method comprises the following steps that the high-pressure tantalum powder is added into a mixed alcohol solution to be stirred; then filtering and cleaning the mixed alcohol solution mixed with the high-pressure tantalum powder by using a filtering piece to obtain primarily treated high-pressure tantalum powder; adding a solid substance obtained by filtering into an acid solution and stirring; filtering the acidic solution of the mixed solid substances by using a filtering piece; and carrying out vacuum drying on a solid substance obtained by filtering to finish the treatment. According to the method, the dissolving effect of the carbon compound under the high-temperature condition is remarkably improved, and deep carbon impurities of the high-pressure tantalum powder are effectively removed. The acetic acid aqueous solution is adopted as an additional treatment step, it is ensured that stubborn carbon impurities can also be effectively removed, and therefore the purity and performance of the high-pressure tantalum powder are greatly improved. After the high-pressure tantalum powder is treated by the whole treatment process, not only is the residue of carbon impurities reduced, but also the quality stability of a final product is greatly improved.

The present application belongs to the field of carbon residue resource utilization, and relates to a W / O emulsion collector for electrolytic aluminum and a preparation and application thereof. The present application adopts kerosene as an external phase, a KCl solution as an internal phase, and an alkyl glycoside (or polyisobutylene ethanolamine) as an emulsifier to prepare a high internal phase W / O emulsion collector, and the high internal phase W / O emulsion collector is used in a flotation decarburization and upgrading process of electrolytic aluminum carbon residue, so that the carbon resource in the carbon residue can be efficiently removed under the condition of low oil consumption, the content of carbon impurities in the cosolvent is reduced, the cosolvent can be recycled and reused in the electrolytic aluminum process, and the present application is of great significance to the sustainable development of the electrolytic aluminum industry and the resource utilization of the carbon residue, and has a good application prospect.

This invention belongs to the field of rare earth permanent magnet materials technology, and relates to a method for preparing sintered NdFeB permanent magnet materials with low carbon content. The preparation method includes the following steps: (1) placing a sintered NdFeB powder compact containing organic additives into the extraction medium of a supercritical extraction device for supercritical extraction, so as to dissolve the organic additive molecules originally adsorbed on the surface of the NdFeB powder particles in the extraction medium; (2) subjecting the supercritically extracted sintered NdFeB powder compact to vacuum sintering and tempering treatment. By using the method for preparing sintered NdFeB permanent magnet materials with low carbon content of this invention, it is possible to significantly reduce carbon impurities in sintered NdFeB materials while ensuring the normal addition of powdered organic additives to NdFeB magnetic powder, thereby comprehensively improving the overall magnetic properties of sintered NdFeB permanent magnet materials.

The invention provides a method and a device for reinforced separation of carbon-containing and arsenic-containing micro-fine particle gold ore with segmented precise regulation and control, and belongs to the technical field of mineral processing. The device comprises a feeding system, a heating system, a suspension roasting furnace, a gas supply system, a detection system and an ore grinding and leaching system. The method comprises the following steps: firstly, crushing and grinding the carbon-containing and arsenic-containing micro-fine particle gold ore, and then drying; conveying the mineral powder into a pre-oxidation chamber of a suspension oxidation roasting furnace, and carrying out pre-oxidation arsenic removal roasting in a suspension state; then feeding into a suspension roasting furnace oxidation chamber, and carrying out decarburization roasting in a suspension state; and after the arsenic-removed calcine is naturally cooled, water is added for ore grinding, ore pulp is subjected to cyanidation leaching, and a gold-containing pregnant solution is obtained. According to the method, the carbon-containing and arsenic-containing micro-fine particle gold ore can be accurately regulated and controlled to be desulfurized and decarbonized under the proper condition, the mass transfer and heat transfer efficiency is high, the arsenic-carbon impurity removal rate is high, the energy consumption and cost of unit treatment capacity are low, the product property is easy to control and stable, and large-scale equipment is easy to realize.

The invention belongs to the technical field of aluminum alloy smelting, and discloses a chromium carbide-based chromium additive for an aluminum alloy and a preparation method and application of the chromium carbide-based chromium additive. The additive is prepared by mixing and pressing 70%-90% of chromium carbide powder, 2%-15% of reducing agent aluminum powder and 5%-20% of composite fluxing slag remover according to a specific ratio. The preparation method comprises the steps of burdening, mixing and compression molding. When the additive is applied, the additive is added into molten aluminum at the temperature of 720-750 DEG C, after alloying reaction, inert gas argon or nitrogen is introduced, and a fluxing slag remover is added for refining treatment. According to the method, direct and efficient utilization of the high-carbon-content and low-cost chromium carbide is achieved for the first time, the actual yield of the chromium element can reach 98% or above under the conventional smelting condition, harmful carbon impurities can be removed by 80% or above, the problems that when the chromium carbide is directly utilized, the carbon content is difficult to remove, and melting is slow are solved, and the production cost is remarkably reduced compared with using of high-purity chromium powder.

The invention provides a preparation method and device of a high-purity carbon nanotube. The carbon nanotube is prepared by utilizing a fluidized bed technology, inert gas and hydrogen are introduced into a long-carbon catalyst obtained in a growth section in a degassing stage for degassing reduction, and the removal rate of carbon impurities on the surface of the catalyst in a purification section can be improved, so that the purity of the carbon nanotube can be improved. The device is simple in structure, the fluidized bed technology is adopted in the growth section, the degassing section and the purification section, the fluidization state of the catalyst in the fluidized bed reactor can be regulated and controlled by controlling the process conditions such as temperature and gas speed, continuous preparation of the carbon nanotubes can be achieved, and the production cost is reduced.

The application relates to the technical field of permanent magnet materials, in particular to a high-resistivity sintered neodymium-iron-boron magnet and a preparation method thereof, which comprises the following steps: (1) smelting raw materials to obtain an alloy ingot; (2) hydrogen breaking the alloy ingot to obtain coarse powder; (3) airflow milling the coarse powder to obtain magnetic powder; (4) compounding the magnetic powder with modified nano-silicon dioxide to obtain composite powder; (5) pressing the composite powder to obtain a green body; and (6) sintering and aging the green body to obtain the high-resistivity sintered neodymium-iron-boron magnet. On the basis of an existing formula process, the nano-silicon dioxide is better dispersed in the grain boundary, so that the conductivity of the magnet is reduced, the high-resistance magnet is obtained, the carbon impurities caused by the silane coupling agent introduced during the preparation of the nano-silicon dioxide are eliminated, and the brittleness of the magnet is prevented from being improved.

The utility model provides a temperature control mechanism for MPCVD equipment, which relates to the technical field of temperature control of the MPCVD equipment and comprises a water circulation system, the MPCVD equipment, a first cooling unit, a second cooling unit, a first circulating water cooling mechanism and a second circulating water cooling mechanism. The water circulation system comprises a circulating pump, and the pump forms a circulation loop through a water inlet pipe and a water outlet pipe; two independent cooling units are adopted, a first cooling unit for strengthening cooling is arranged in a central area, gradient cooling is conducted on plasma through a cooling medium with a high heat conductivity coefficient, and graphitization phase change induced by local high temperature is effectively restrained; the temperature of the marginal area is controlled by adopting a dynamic temperature control technology, so that the sudden drop of the deposition rate and the generation of amorphous carbon impurities caused by excessive cooling are avoided; the problems that the substrate of the existing MPCVD equipment generally adopts an integral cooling structure design, the temperature rising speeds of the center and the peripheral partition of the substrate are inconsistent, the phenomenon of non-uniform temperature distribution occurs after a certain time, and crystal defects are caused by local temperature difference are solved.

The present invention, by including a specific amount of impurity carbon, provides a crystalline silicon nitride powder that is easily sintered and makes it possible to produce a silicon nitride sintered body having excellent mechanical strength or thermal conductivity. Also provided by using this silicon nitride powder is a silicon nitride sintered body that is easily sintered and has excellent mechanical strength or thermal conductivity. The present invention also provides a method for producing a silicon nitride sintered body that is easily sintered and has excellent mechanical strength or thermal conductivity. Provided is a crystalline silicon nitride powder containing silicon nitride, carbon, and oxygen, in which the mass ratio Cp of the carbon to the whole powder is 0.200 mass% or less, the mass ratio C1 of a first volatile carbon detected at from 100°C to less than 700°C measured by temperature-programmed morphology analysis is from 0.001 mass% to 0.030 mass%, and the mass ratio C2 of a second volatile carbon detected at from 700°C to 1200°C measured by temperature-programmed morphology analysis from 0.005 mass% to 0.060 mass%.

The invention discloses a preparation method and application of a high-purity lithium sulfide material, and belongs to the technical field of inorganic material preparation and advanced energy storage. According to the method, precursor molecular level homogenization design, program temperature control segmented calcination and an inert atmosphere liquid phase deep purification process are innovatively integrated, specifically, lithium sulfate is used as a lithium source, high-activity carbon is used as a reducing agent, citric acid is used as a multifunctional additive, and after nanoscale mixing, a precursor is prepared; two-stage calcination of low-temperature carbon skeleton construction and high-temperature deep reduction is carried out in an inert atmosphere; and finally, carbon impurities are selectively removed by using absolute ethyl alcohol in a glove box. The material can be used as a key precursor to synthesize a high-performance sulfide solid electrolyte (the ionic conductivity is gt, 3.2 mS / cm), can also be used as an efficient pre-lithiation additive to improve the first coulombic efficiency of a battery, or is directly used as a positive electrode of a lithium-sulfur battery, and shows excellent electrochemical performance. The method is low in process cost, stable, controllable and easy for large-scale production.

Methods for forming a magnesium oxide layer are disclosed. The disclosed method includes performing a cyclic deposition process to form a magnesium oxide layer having a reduced or low carbon impurity concentration. Also disclosed are methods for forming a magnesium-indium-zinc oxide layer comprising a magnesium oxide component having a reduced or low concentration of carbon impurities.