83results about "Metal borides" patented technology

The invention discloses medium-entropy MAB-phase ceramic powder and a preparation method thereof, and belongs to the technical field of ceramic material preparation. The chemical formula of the ceramic powder is (Cr1 / 3Mn1 / 3Fe1 / 3) 2AlB2, and the ceramic powder is structurally characterized in that three transition metal atoms of Cr, Mn and Fe are in random solid solution distribution at an M position. The preparation method of the material comprises the following steps: taking Cr powder, Mn powder, Fe powder, Al powder and B powder as raw materials, burdening according to a stoichiometric molar ratio in a chemical formula (Cr1 / 3Mn1 / 3Fe1 / 3) 2AlxB2 (wherein x is equal to 1.0-1.3), uniformly mixing, and sintering in a non-pressure tube furnace by adopting a two-stage heating sintering process. And crushing, drying and sieving the sintered product to obtain the ceramic powder. According to the invention, excessive aluminum powder is added to compensate high-temperature volatilization, and a two-stage sintering process is combined, so that the generation of an impurity phase is effectively inhibited, and a high-purity target product is successfully prepared. The synthesis method is simple in process, low in equipment requirement and suitable for large-scale production, and a material basis is provided for application of the medium-entropy MAB phase ceramic in the fields of electromagnetic functions, high-temperature environments and the like.

The present invention provides: a MgB2 superconducting wire that has a barrier layer of highly uniform thickness covering a MgB2 core and that reduces MgB2 filament defects and is suitable for thinning and lengthening; a MgB2 superconducting wire manufacturing method for manufacturing the same; a superconducting coil using the same; and a magnetic generator including the superconducting coil. A MgB2 superconducting wire (200) comprises: a core material (210); a MgB2 filament (220) in which a MgB2 core (221) is covered with a barrier layer (222); and a metal sheath (230). The MgB2 filament (220) has a barrier layer (222) thickness on the outer peripheral side of the wire not more than three times the barrier layer (222) thickness on the core side of the wire. The method for manufacturing the MgB2 superconducting wire includes a step for forming a single core wire, a step for forming an embedded material, a surface reduction processing step, and a heat treatment step. The embedded material is formed by arranging the single core wire in a recess formed in the outer surface of the core material or by incorporating a spacer in a gap.

The invention relates to a method for fabricating a two-dimensional (2D) heterostructure comprising depositing graphene on a substrate in an ultrahigh vacuum (UHV) chamber at a first temperature and a first chamber pressure to form sub-monolayer graphene on the substrate; and subsequently depositing borophene onto the sub-monolayer graphene on the substrate in the UHV chamber at a second temperature and a second chamber pressure so as to couple the borophene with the graphene on the substrate to form a 2D borophene-graphene heterostructure comprising lateral and / or vertical heterostructures.

The invention provides high-purity superfine titanium diboride and a preparation method thereof, and relates to the field of titanium diboride preparation. The method comprises the following steps: mixing boron oxide, titanium hydride, a carbon source, nano rare earth oxide and an organic solvent, and drying to obtain a mixture; in a vacuum environment, performing first roasting on the mixture to obtain a first roasted material; and in an oxygen-containing atmosphere, carrying out second roasting on the first roasting material to obtain the high-purity superfine titanium diboride. In the first roasting process, boron oxide, titanium hydride and a carbon source are completely melted and fully contacted, then further, the carbon source forms a carbon skeleton, the contact area between the melted boron oxide and titanium hydride and the carbon skeleton is further enlarged, liquid-liquid mixing and the increase of the contact area can reduce the reaction kinetic conditions, the reaction temperature is greatly reduced, and the reaction time is greatly shortened. The particle size of the generated titanium diboride is reduced, and the molten boron oxide and titanium hydride react on the porous carbon skeleton in a liquid-liquid form to generate the high-purity superfine titanium diboride.

Provided are methods of producing cobalt-based nanoparticles (CoxBy NPs) of a pre-selected diameter. The methods include reducing Co2+ ions with a sodium borohydride (NaBH4) solution having a selected ratio of tetrahydroxyborate (B(OH)4−) to tetrahydroborate (BH4−) based on the pre-selected diameter, where the ratio of B(OH)4− to BH4− is positively correlated with the pre-selected diameter. Also provided are methods of using the CoxBy NPs to produce hollow metal nanospheres (HMNs). Methods of producing CoxBy NP core / metal shell structures are also provided, such methods including combining in an anaerobic galvanic exchange reaction a deaerated solution including CoxBy NP scaffolds and a deaerated solution including a metal. Also provided are methods of producing HMNs from the CoxBy NP core / metal shell structures. Compositions and kits that find use in practicing the methods of the present disclosure and using HMNs produced in accordance with the methods of the present disclosure, are also provided.

The invention belongs to the technical field of preparation of high-purity cobalt boride, and particularly provides a preparation method of high-purity superfine cobalt boride powder, which comprises the following steps: 1) mixing Co3O4 with isopropanol, sanding and crushing to obtain Co3O4 slurry; b4C and isopropanol are mixed, sanded and crushed to obtain B4C slurry; then mixing the Co3O4 slurry with the B4C slurry and carbon black at a high speed to obtain a mixture; 2) sintering the mixture under the protection of inert gas to obtain a sintered material, and 3) scattering and sieving the sintered material to obtain the CoB. The CoB prepared by the invention has the advantages of low impurity content, small particle size and uniformity.

The invention discloses a diboride hollow microsphere and a preparation method thereof, and belongs to the technical field of new material preparation. The invention aims to solve the problem of preparing diboride hollow microspheres with excellent performance. The preparation method comprises the following steps: preparing precursor sol; performing gelatinization treatment on the precursor sol in a high-temperature closed environment, performing normal-pressure drying in an open environment to obtain a diboride hollow microsphere precursor, grinding the diboride hollow microsphere precursor into powder in a crucible, then performing secondary grinding in an aqueous solution containing PEG-4000, performing ultrasonic treatment after uniform grinding, and then performing vacuum drying to obtain the diboride hollow microsphere. And carrying out high-temperature boron-carbon thermal reduction reaction on the obtained diboride hollow microsphere precursor to generate diboride hollow microspheres, and carrying out solution treatment on the diboride hollow microspheres under a high-temperature condition to obtain a final product. The preparation of the high-quality diboride hollow microspheres is realized, the high-quality diboride hollow microspheres have good dispersity, and the product forming rate can reach 80% or above.

The invention belongs to the technical field of photocatalyst composite materials, and particularly relates to a covalent bond bonded MoBTx / CdS composite material and a preparation method and application thereof.According to the MoBTx / CdS composite material, rod-shaped CdS and two-dimensional layered MoBTx are compounded through an in-situ growth strategy, covalent bonding between Mo atoms and S atoms is achieved at an interface, and the MoBTx / CdS composite material is obtained. Therefore, a strong-coupling heterogeneous interface is constructed. The covalent bond mediated composite structure can significantly enhance visible light absorption and optimize carrier separation and transmission kinetics, thereby improving the activity and stability of hydrogen production by photocatalytic decomposition of water. The material is excellent in environmental adaptability and can keep good hydrogen evolution performance under complex water quality and low-temperature conditions. The research provides a new interface engineering idea for designing an efficient and stable semiconductor-metal boride photocatalyst.

The application provides a preparation method of high-purity superfine diboride powder and relates to the field of metal borides. The preparation method comprises the following steps: introducing BCl3 and H2 into a vacuum environment to obtain a mixed gas; mixing the mixed gas and metal wires and performing electric explosion treatment to obtain a reaction powder; and performing passivation ball milling treatment on the reaction powder in a mixed atmosphere of argon and oxygen to obtain the high-purity superfine diboride powder; and the metal wires comprise at least one of titanium wires, magnesium wires and aluminum wires. The method does not introduce by-products and impurities in the whole process, the obtained diboride powder is small in particle size, uniform in distribution and free of agglomeration, the preparation method is short in process and high in efficiency, and the method has a good industrialization prospect.

The invention relates to a method for synthesizing calcium hexaboride micro-nano powder by electric field and magnetic field coupling auxiliary combustion, which mainly comprises the following steps: by taking calcium hydroxide, boric oxide and magnesium powder as raw materials, carrying out electric field and magnetic field coupling auxiliary combustion synthesis to obtain a reaction product; and then, carrying out acid pickling on a reaction product to obtain the unique calcium hexaboride micro-nano material with the hollow cubic structure. In the process of combustion synthesis of calcium hexaboride, under the coupling influence of an electric field and a magnetic field, the prepared calcium hexaboride micro-nano powder shows unique hollow cubic structural characteristics, and the structural characteristics enable the calcium hexaboride micro-nano powder to have the advantages of high specific surface area, light weight, porous neutron absorption and the like; the method has important application prospects in the fields of aerospace, high-end manufacturing, nuclear industry and the like.

The invention relates to the technical field of electrochemical energy storage, in particular to a Li / Na ion battery negative electrode material heterojunction as well as a construction method and a performance prediction method thereof, the negative electrode material is a two-dimensional MoB / MoS2 Van der Waals heterojunction, and is formed by compounding MoB with high conductivity and MoS2 with high theoretical capacity. A built-in electric field induced by a work function difference exists at an interface of the heterojunction, so that electron transmission and ion migration can be remarkably accelerated; meanwhile, volume change in the charging and discharging process is effectively buffered through tight interface coupling and B-S covalent interaction, and the structural stability is enhanced. Through systematic evaluation of a first principle calculation method, the MoB / MoS2 heterojunction shows high theoretical specific capacity, low ion diffusion barrier, appropriate open-circuit voltage and excellent structural and mechanical stability, and is a high-performance Li / Na ion battery negative electrode material with great potential.

The application is a preparation method and application of ternary metal boride MoCoB electrocatalyst. 2 / 3 Y 1 / 3 )2AlB2 as a precursor, cobalt bromide as an etchant and a cobalt source, one-step removal of Al / Y and in-situ doping of Co to prepare MoCoB electrocatalyst with Mo / Co / B three-site synergy; Mo site efficiently adsorbs and activates nitrate, Co site dissociates water to provide active hydrogen, and B site builds an electronic bridge through orbital hybridization, thereby strengthening the electron transfer between active sites and the directional migration of active hydrogen. The electrocatalyst prepared by the application shows a faradaic efficiency of up to 61890 μg h ‑1 mg ‑1 and 98.73% in the reaction of nitrate reduction to synthesize ammonia, not only realizing high yield and high faradaic efficiency at the same time, but also showing the industrial application potential of green and sustainable synthesis of ammonia.

The application discloses a kind of powder preparation devices of titanium diboride for lithium battery preparation, including preparation container, controller, gas pressure gauge and servo motor, the output end of the servo motor passes through preparation container and is fixedly connected with ball screw nut pair, kettle wall contact component is arranged outside the ball screw nut pair, specifically relates to titanium diboride powder preparation technical field, the dispersion component rotation is realized when screw shaft axial rotation and is driven to realize the dispersion stirring operation of kettle body bottom material, the preparation rate of material can be promoted by dispersion component rotation and drives material stirring, and the purpose of kettle body wall scanning and dispersion component dispersion material can be completed under the premise that only one servo motor works, so that the purpose of promoting material preparation rate and reducing material loss can be simultaneously realized in energy-saving environment, effectively realize the purpose of reducing cost and improving yield and product quality.

The invention belongs to the technical field of electrochemistry and new energy, and particularly relates to a universal preparation method of MBene based on NH4HF2 protection-etching synergy and application of MBene in a lithium-sulfur battery. The preparation method comprises the following steps: mixing an MAB phase precursor and an NH4HF2 aqueous solution, and carrying out hydrothermal reaction to obtain MBene. Accurate etching of the Al layer in the MAB phase precursor and in-situ protection of the transition metal M layer can be effectively achieved, the method does not depend on a strong corrosive system and has universality, the prepared MBene serves as a positive electrode carrier and a diaphragm modification layer of a lithium-sulfur battery, the adsorption catalysis capacity on polysulfide can be remarkably enhanced, and the service life of the lithium-sulfur battery is prolonged. And the purpose of improving the rate capability and the cycling stability of the lithium-sulfur battery is achieved.

This invention relates to the field of hydrogen energy storage technology, specifically disclosing a layered transition metal boride-modified lithium-magnesium-boron-hydrogen composite hydrogen storage material and its preparation method. This material uses 2LiH+MgB2 as a matrix and adds layered Mo... 4 / 3 B2 MBene was prepared as a modifier; Mo was used as a modifier. 4 / 3 B2 MBene by (Mo 2 / 3 Y 1 / 3 The 2AlB2 MAB phase precursor was prepared by selectively etching with HF to remove Al and Y atoms, followed by intercalation, layering, and freeze-drying. This invention utilizes mechanical ball milling to process Mo... 4 / 3 B2 MBene introduces the Li-Mg-B-H (LMBH) composite system, utilizing Mo 4 / 3 The unique layered structure of B2 MBene, combined with its inherent catalytic activity, significantly reduces the hydrogen desorption temperature of the LMBH system and improves its hydrogen desorption kinetics and cycle stability. This material can release 8.1 wt% H2 within 60 minutes at 420℃, and maintains a capacity retention of 68.7% after three cycles. Its performance surpasses that of bulk MoB-doped and undoped LMBH systems, providing a new approach for performance regulation of lightweight hydrogen storage materials and demonstrating promising practical application prospects.

A layered-oxide positive electrode active material may have a molecular formula of NaxMnaFebNicMdNeO2-δQf, where a doping element M is selected from at least one of Cu, Li, Ti, Zr, K, Sb, Nb, Mg, Ca, Mo, Zn, Cr, W, Bi, Sn, Ge, or Al, a doping element N is selected from at least one of Si, P, B, S, or Se, a doping element Q is selected from at least one of F, Cl, or N, 0.66≤x≤1, 0<a≤0.70, 0<b≤0.70, 0<c≤0.23, 0≤d<0.30, 0≤e≤0.30, 0≤f≤0.30, 0≤δ≤0.30, a+b+c+d+e=1, 0<e+f≤0.30, 0<(e+f) / a≤0.30, 0.20≤d+e+f≤0.30, and (b+c) / a≤1.5.

The present application belongs to the field of development of fuel cell cathode materials, and relates to a preparation method of a boron-chromium-nitrogen co-doped carbon-based oxygen reduction fuel cell cathode material prepared by modifying a white bark powder as a carbon source precursor with bayberry tannin. The hydrolysis product of the white bark powder is gelatin with rich active groups, and the gelatin molecular structure is rich in active groups such as amino groups and hydroxyl groups, and can efficiently complex various metal ions, so that the white bark powder can be used as an anchor for various nano-metal active ingredients to prepare an electrocatalyst carrier with high catalytic activity and long service life. In the present application, the gelatin, which is the hydrolysis product of the white bark powder, is used as a base material, and is compounded with boron and chromium modified by bayberry tannin to prepare a high-performance low-cost bayberry tannin modified boron-chromium-nitrogen co-doped carbon-based oxygen reduction fuel cell cathode material through pyrolysis.

The application provides a hard carbon composite negative electrode material and a preparation method and a lithium ion battery thereof, and relates to the technical field of lithium ion batteries.The preparation method comprises the following steps: adding nano silicon, a boron source and a surfactant into an alcohol solvent, performing ultrasonic dispersion, and obtaining a suspension; adding a titanium source into the suspension, and obtaining a mixed reaction solution; placing the mixed reaction solution into a hydrothermal kettle, performing hydrothermal treatment at 180-250 DEG C, and obtaining a hydrothermal product; mixing the hydrothermal product with a hard carbon precursor, and obtaining a mixture; performing calcination on the mixture at 1000-1500 DEG C under an inert atmosphere, and obtaining the hard carbon composite negative electrode material.The preparation method of the hard carbon composite negative electrode material provided by the application uses nano silicon, a boron source and a titanium source as raw materials, and the prepared composite negative electrode material is coated with TiC on the outside of the nano silicon, which not only helps to improve the conductivity of the composite negative electrode material, but also effectively alleviates the volume effect of silicon in the charging and discharging process.

The application belongs to the technical field of electrochemical energy storage, and relates to electrochemically activated vanadium diboride, a preparation method thereof and application of the vanadium diboride in a water-based energy storage positive electrode material. The method comprises the following steps: assembling a vanadium diboride positive electrode, a separator, a negative electrode and a water-based electrolyte into an energy storage system; and activating by using a chronocoulometry method, a repeated cyclic voltammetry method, a chronopotentiometry method or a multiple constant current charge-discharge cycle method to obtain an in-situ electrochemically activated vanadium diboride positive electrode material. The electrochemically activated vanadium diboride positive electrode is applied to a Zn 2+ , Li + , NH4 + , Mg 2+ , etc. water-based energy storage system, and exhibits high electrochemical activity. For example, a zinc ion battery assembled at a current density of 0.1 A / g has a specific capacity of 331 mAh / g. The electrochemically activated vanadium diboride water-based energy storage positive electrode material provided by the application has high specific capacity and long cycle life, is low in preparation cost, simple in preparation process and suitable for large-scale industrial production.

The invention discloses small-particle-size low-oxygen ZrB-SiC complex-phase powder, a one-step controllable synthesis method thereof and application of the powder in high-performance ceramics, and belongs to the technical field of ultra-high-temperature ceramic materials. According to the method, ZrO, BC, elemental Si and activated carbon are used as raw materials, and the ZrB-SiC complex-phase powder is prepared through an optimized boron-carbon thermal reduction method. The core innovation point is that the specific raw material ratio design is as follows: n (ZrO): n (BC): n (Si): n (C) = 3: (1.65-1.95): (0.5-1.0): (4.95-6.05), the most preferable ratio is 3: 1.8: 1: 5.5, and heat preservation is performed for 60 minutes at 1500 DEG C in an inert atmosphere. The design effectively compensates volatilization of intermediate phase BO, and ensures complete reaction. The prepared multiphase powder has the prominent advantages of small particle size (D100lt, 0.71 [mu] m), low oxygen content, high purity and accurate regulation and control of the ratio of two phases, and ZrB and SiC two-phase interfaces in the powder are in semi-coherent combination. The high-performance ZrB-SiC composite ceramic can be prepared by using the self-made powder as a raw material and adopting spark plasma sintering (SPS), and the relative density of the high-performance ZrB-SiC composite ceramic is up to 99.24% or above.

The application relates to the technical field of ultrahigh-temperature ceramic materials, and discloses a nano ZrB2-SiC composite ceramic powder based on gradient proportioning regulation and a low-temperature preparation method thereof; in view of the technical bottlenecks such as high reaction temperature (>=1600 DEG C), large powder particle size (>=10 mu m) and difficult two-phase proportion regulation in the prior art, the application innovatively proposes a gradient temperature-subsection proportioning preparation process. By accurately controlling the raw material proportioning of n(ZrO2):n(B4C):n(Si):n(C)=3:(1.8-2.0):1:(5.5-6.0), adopting a two-stage heating procedure (SiC crystal nuclei are preferentially generated at 1200 DEG C, and ZrB2 synthesis is completed at 1500 DEG C), the low-temperature and high-efficiency synthesis of ZrB2-SiC composite powder is realized in a single process. The complete reaction temperature is successfully reduced to 1500 DEG C, the average particle size of the obtained powder is 0.5-0.6 mu m, the oxygen content is <=0.8 wt%, and the ZrB2:SiC molar ratio can be accurately regulated in the range of 2:1 to 4:1 by adjusting the Si content. The ZrB2 (101) plane and the SiC (111) plane in the powder form a semi-coherent interface, and the crystal lattice distortion rate is <=3%.

This invention relates to a high-entropy tetraboron / hexaboride material and its preparation method, belonging to the field of ultra-high temperature ceramic materials technology. The nominal molecular formula of the material is (Y0). 0.2 La 0.2 Ho 0.2 Er 0.2 Yb 0.2 )B4 / (Y 0.2 La 0.2 Ho 0.2 Er 0.2 Yb 0.2 B6, and (Y) 0.2 La 0.2 Ho 0.2 Er 0.2 Yb 0.2 B4 and (Y) 0.2 La 0.2 Ho 0.2 Er 0.2 Yb 0.2 The mass ratio of B6 is 38.91–49.50:61.09–50.05. The raw material powder is wet-mixed using an acoustic resonance mixer until homogeneous, then dried; subsequently dry-pressed and calcined under vacuum at a constant temperature. When powder production is required, the agglomerates are broken up using the acoustic resonance mixer. This invention, by adjusting the elemental ratio, synthesizes La-based high-entropy boride powder for the first time. The resulting material has clear crystal morphology, controllable proportions, and uniform elemental distribution, retaining both high-entropy solid solution components and good thermal stability. Compared to single-component materials, this material exhibits superior oxidation resistance due to selective oxidation during the high-entropy effect. The preparation method can uniformly disperse the raw material powder, is simple, and easily scales up production.

The invention belongs to the field of electrochemistry, and particularly relates to a zirconium diboride composite positive electrode material and a preparation method and application thereof.The preparation method comprises the steps that a zirconium source and a boron source are mixed and then subjected to high-temperature heat treatment in an inert gas atmosphere in an environment with a reducing agent, and nanometer zirconium diboride is obtained; the preparation method comprises the following steps: fully dispersing nano zirconium diboride and activated carbon in a solvent, and fully grinding to obtain the zirconium diboride composite material. The electrode material prepared by the method is high in stability and good in cycle performance.

The application provides a rare earth hexaboride submicron crystal or nanocrystal material and a preparation method thereof. 1‑ x RE x )B6 powder, La powder or RE powder, MeB2 powder is prepared through SPS sintering, the content of the La powder or RE powder is 1wt.%-5wt.%, the content of the MeB2 powder is 8wt.%-30wt.%, and the rest is (La 1‑x RE x )B6 powder, RE is Ce, Pr, Nd, Sm, Eu, Gd, Ca, S or Ba, Me is Ta, Cr, Nb, V, Hf, Ti or Zr, and 0 1‑x RE x )B6 submicron crystal is successfully obtained at a working temperature through SPS sintering in combination with La / RE sintering aids and MB2 powder with high melting point and high elastic modulus, and the thermal emission performance and mechanical properties of the material are improved.

The application discloses a novel high-efficiency Fe2AlB2@Al2O3 high-temperature absorber, a preparation method and application, the microstructure of the high-temperature absorber is nanometer layer, the micro-layer thickness is 10-50 nm, the layered Fe2AlB2 is coated with an Al2O3 shell layer, and the shell layer thickness is 5-10 nm. The preparation method of the high-temperature absorber is as follows: weighing powder, high-energy ball milling, laser rapid sintering, and plasma ball milling plus in-situ self-generation. The high-temperature absorber can serve in a 600-800 DEG C environment for a long time, exhibits good wave-absorbing performance, has the characteristics of a wide absorption frequency band and high wave-absorbing efficiency, and the preparation method has the advantages of short synthesis time, low energy consumption, high efficiency and high purity.

The application discloses monodisperse rare earth boride nanomaterials with a size less than 20 nm, a preparation method and application thereof, and the phase state of the rare earth boride nanomaterials is REB6 or REB4; the preparation method comprises the following steps: S1, weighing compound raw materials containing RE elements and compound raw materials containing B elements respectively; S2, adding an additive and grinding thoroughly; S3, then performing a reaction under the protection of an inert gas; S4, after the reaction is completed, adding excessive methanol, performing centrifugal separation after no bubbles are generated, and reserving a precipitate A; S5, adding dilute hydrochloric acid for soaking, performing centrifugal separation again, and reserving a precipitate B; S6, washing the precipitate B with deionized water, drying, and obtaining the rare earth boride nanomaterials. The application adopts a normal-pressure low-temperature preparation method, and pure-phase rare earth hexaboride nanocrystals can be obtained at normal pressure and a temperature as low as 270 DEG C, and any active metal element is not needed to be introduced in the preparation process.

The application relates to the technical field of hexagonal MBenes material preparation, in particular to a two-dimensional hexagonal transition metal boride h-MBenes material, a preparation method and application thereof. The molecular formula of the h-MBenes material is Hf x B y T z (T=H, O, F, Cl or OH), the h-MBenes phase material has a hexagonal crystal structure and is formed by alternately stacking transition metal hafnium layers and graphene-like boron layers, and the h-MBenes phase material is easy to be functionalized. The hexagonal ternary layered transition metal boride h-MAB phase material is used as raw material, the hexagonal ternary layered transition metal boride h-MAB phase material is etched by using a wet chemical method or a molten salt method, and a two-dimensional hexagonal transition metal boride h-MBenes material is obtained, the method is simple and effective, the raw material is easy to obtain and low in price, and the method has important industrial application prospects. The application also discloses possible applications of the h-MAB phase for preparing the h-MBenes material, and the results show that the h-MBenes material has good conductivity and excellent electrochemical performance.

This provides a superconducting wire with high Tc and excellent flexibility. [Solution] A superconducting wire comprises a core material formed of a first material having superconducting properties, and a covering material formed of a second material different from the first material, which also has superconducting properties and covers the core material. In this superconducting wire, one of the first and second materials is MgB2, and the other of the first and second materials is a Cu oxide-based superconducting material.

To provide a lithium diboride sheet-containing substance having a large amount of introduced metal and not comprising hydrogen, and a manufacturing method of the lithium diboride sheet-containing substance.SOLUTION: A lithium diboride sheet-containing substance has a two-dimensional network consisting of (LiB2)n (n≥12), wherein the two-dimensional network has a mesh shape in which boron atoms are arranged in a hexagonal ring and hexagons formed by the boron atoms are connected, and comprises a site where two lithium atoms sandwich a central part of a hexagon of boron.SELECTED DRAWING: None

The present invention addresses the problem of providing a superconducting material which can be used in a liquid hydrogen level meter, has a simple production method, and can obtain reproducibility. This superconductor is characterized by being composed of a metal compound in which the molar ratio of magnesium (Mg) to boron (B) is 1: 2, not containing SiC, and by having a critical temperature (Tc) at which the electrical resistance substantially becomes zero of about 32 K to about 34 K. Therefore, the liquid level meter for liquid hydrogen, which is simple in manufacturing method and capable of obtaining reproducibility, can be realized.