68 results about "Magnesium doping" patented technology

The invention discloses a Ga2O3-baesd metal oxide semiconductor field effect transistor with good heat dissipation performance and a preparation method thereof, and belongs to the technical field of power semiconductor devices and preparation thereof. The device is formed by parts of a substrate, a Ga2O3 buffering layer, a Ga2O3 channel layer, a Ga2O3 source, a drain region, an Al2O3 insulation layer and a metal electrode, and is characterized in that the substrate is Si monocrystalline; a nitride and oxide mixed multilayer structure is prepared between the substrate and the Ga2O3 buffering layer; and the mixed multilayer structure is formed by a GaN-serial multilayer structure film, a Ga2O3 oxidation thin layer, an involuntary doped Ga2O3 lower buffering layer and a magnesium doped Ga2O3 semi-insulation layer. According to the invention, a heteroepitaxy problem of Ga2O3 materials is solved; disadvantages of poor heat dissipation performance and high selling price of the Ga2O3 monocrystalline substrate used by the current Ga2O3-baesd metal oxide semiconductor field effect transistor are overcome; and advantages of mature technology, low selling price, easy integration and good heat dissipation of the Si material can be used, so the provided Ga2O3-baesd metal oxide semiconductor field effect transistor is quite highly practical.

The invention discloses an activation method of magnesium-doped nitride-based materials and luminescent diode P type gallium nitride, which comprises using an ICP plasma to process magnesium-doped nitride-based materials or luminescent diode P type gallium nitride, wherein reaction atmosphere comprises gas which contains oxygen element and mixed gas which contains oxygen element gas, or mixed gas of above gas with nitrogen, helium or argon gas, wherein the density of the plasma is between 1011-3 and 1012cm-3, then, removing oxidizing substance generated through the above reaction, and doing 400-600 EDG C high-temperature annealing to the materials. The activation method gets high-cavity density of magnesium-doped GaN materials, and improves the activation efficiency of magnesium-doped p-GaN.

A III-nitride-based light emitting device having a multiple quantum well (MQW) structure and a method for fabricating the device, wherein at least one barrier in the MQW structure is doped with magnesium (Mg). The Mg doping of the barrier is accomplished by introducing a bis(cyclopentadienyl)magnesium (Cp2Mg) flow during growth of the barrier using metalorganic chemical vapor deposition (MOCVD). The barriers of the MQW structure may be undoped, fully Mg-doped or partially Mg-doped. When the barrier is partially Mg-doped, only portions of the barrier are Mg-doped to prevent Mg diffusion into quantum wells of the MQW structure. The Mg-doped barriers preferably are high Al composition AlGaN barriers in nonpolar or semipolar devices.

The invention relates to a preparation method of a three-dimensional graphene / tungsten-based nanosheet / magnesium doped zinc oxide layer-by-layer assembly structure. According to the method, graphene, tungsten-based nanosheets, zinc acetate and magnesium acetate are used as raw materials, deionized water is used as a solvent and oxalic acid is used as a complexing agent, and a co-precipitation method and subsequent heat treatment are used to prepare the three-dimensional graphene / tungsten-based nanosheet / magnesium doped zinc oxide layer-by-layer assembly structure. The most important characteristic of the invention is that a mechanical shearing method is used to prepare a water-soluble tungsten-based nanosheet dispersed solution, and the three-dimensional graphene / tungsten-based nanosheet / magnesium doped zinc oxide layer-by-layer assembly structure is obtained in a water solution; the preparation process is simple and easy to realize scale production; meanwhile, the three-dimensional graphene / tungsten-based nanosheet structure has a good synergistic effect, and is more favorable for the separation of photo-induced electrons and electron-hole pairs in comparison with a homogenous material; the three-dimensional graphene / tungsten-based nanosheet / magnesium doped zinc oxide layer-by-layer assembly structure has good photocatalytic performance and can be applied to the fields of sewage treatment, photolysis of water, air purification and solar cells.

The invention provides an LED epitaxial layer, a growth method of the LED epitaxial layer and an LED chip. The LED epitaxial layer comprises an N-type confinement layer, an MQW layer and a P-type confinement layer, wherein the N-type confinement layer, the MQW layer and the P-type confinement layer grow in order, the MQW layer comprises a plurality of structure units, and each structure unit comprises an InGaN layer and a GaN layer. The LED epitaxial layer is characterized in that the inside of each structure unit further comprises at least one magnesium doping layer. According to the LED epitaxial layer, the magnesium doping layers are additionally arranged in multiple quantum wells, surfaces of GaN potential barriers are coarse, growth of InGaN potential wells is influenced, InGaN cross growth is inhibited, InGaN three-dimensional growth is promoted, and accordingly the number of quantum dots in InGaN is increased, and light-emitting efficiency of the LED chip is improved by 5%-6%.

The invention discloses a light emitting diode epitaxial wafer and a manufacturing method therefor, and belongs to the technical field of a semiconductor. The epitaxial wafer comprises a substrate, a buffer layer, a non-doped gallium nitride layer, an N type gallium nitride layer, a multi-quantum-well layer, an electron barrier layer and a P type gallium nitride layer; the electron barrier layer comprises a first sub layer, a second sub layer and a third sub layer; the first sub layer comprises multiple first aluminum gallium nitride layers and multiple second aluminum gallium nitride layers which are stacked alternately; the second sub layer comprises multiple third aluminum gallium nitride layers and multiple first indium gallium nitride layers which are stacked alternately; the third sub layer comprises gallium nitride layer and second indium gallium nitride layers which are stacked alternately; the aluminum doping concentration in the first aluminum gallium nitride layers and the second aluminum gallium nitride layers is greater than that in the third aluminum gallium nitride layers; the first indium gallium nitride layers, the gallium nitride layers and the second indium gallium nitride layers are all doped with magnesium; the magnesium doping concentration in the first indium gallium nitride layers is lower than that in the gallium nitride layers and the second indium gallium nitride layers. By virtue of the light emitting diode epitaxial wafer and the manufacturing method therefor, hole injection can be improved and LED light emitting efficiency can be improved.

The invention relates to a magnesium-containing hydroxyapatite coating on the surface of a medical material. The coating comprises Ca10(PO4)6(OH)2 and Mg10(PO4)6(OH)2, wherein the Mg10(PO4)6(OH)2 accounts for 0-10% of the total mass of the coating. The preparation method of the magnesium-containing hydroxyapatite coating on the surface of the medical material comprises the following steps: a, hydro-thermal treatment; b, magnesium doping treatment; and c, hydro-thermal treatment. The preparation method of the magnesium-containing hydroxyapatite coating on the surface of the medical material is simple and easy to operate, and the magnesium-containing hydroxyapatite coating on the surface of the medical material has the functions of inducing bone tissue regeneration, and regulating osseous growth and remodeling.

The invention belongs to the technical field of lithium ion battery materials, and discloses a zirconium-magnesium doping and zirconium coating double-modified nickel-cobalt-manganese ternary precursor and a preparation method thereof. According to the preparation method, Zr and Mg are introduced into the ternary precursor for doping, Zr is introduced for coating at the later stage of reaction, a complexing control crystallization coprecipitation method is adopted, and the zirconium-magnesium doping and zirconium coating dual-modified nickel-cobalt-manganese ternary precursor is prepared by controlling parameters such as the pH value, the ammonia concentration and the reaction temperature of a reaction system. According to the invention, Zr, Mg doping and Zr coating are introduced into the ternary precursor, the positive electrode material inheriting the performance is stable in cycle performance, good in capacity retention rate and excellent in rate performance, meanwhile, the single crystal material has the characteristics of compact internal structure and no crack, the volume effect and crack generation can be effectively inhibited in the fast charging process, and the development requirements of the electric vehicle industry can be met.

The invention discloses a magnesium-doped enhanced GaN-based HEMT device and a preparation method thereof. The method comprises the following steps: (1) a gate electrode contact window is formed abovean AlxGa1-xN barrier layer in a photoetching mode; (2) metal magnesium is deposited on the photo-etched surface by adopting an electron beam evaporation / thermal evaporation / magnetron sputtering method; (3) the unexposed photoresist is stripped by adopting a stripping process; (4) a thermal annealing process is carried out on an epitaxial wafer deposited with magnesium for performing diffusion doping of thermal annealing; and (5) the annealed surface metal magnesium is removed by preparing dilute hydrochloric acid to obtain the enhanced GaN-based HEMT device. According to the method, the metal magnesium thermal diffusion technology is utilized to realize the P-type doping of the AlxGa1-xN barrier layer below the gate electrode to prepare the enhanced GaN-based HEMT device. The preparationmethod has the advantages of being simple in process and low in cost, and has important significance for realizing the high-performance GaN-based HEMT devices.

A method for growing an improved quality device by depositing a low temperature (LT) magnesium (Mg) doped nitride semiconductor thin film. The low temperature Mg doped nitride semiconductor thin film may have a thickness greater than 50 nm. A multi quantum well (MQW) active layer may be grown at a growth temperature and the LT Mg doped nitride semiconductor thin film may deposited on the MQW active layer at a substrate temperature no greater than 150° C. above the growth temperature.

The present invention relates to a method for preparing a ferrite superparamagnetic nano particle engineered by magnesium doping, and a technique for applying it to hyperthermia cancer cell treatment and the heat shock protein (HSP) self-defense mechanism.

The invention belongs to the technical field of electrochemistry, and particularly relates to a high-energy-density lithium iron phosphate battery. A positive electrode active material is selected from titanium / magnesium-doped lithium iron phosphate, the surface density of a positive plate is 190-210 g / m<2>, the compaction density is greater than or equal to 2.60 g / cc, a negative electrode active material is carbon-coated single particle and secondary particle needle coke blend artificial graphite, and the compaction density of a negative plate is greater than or equal to 1.70 g / cc. The density of the electrolyte is equal to 1.15 g / cc, the wall thickness of the aluminum shell body is 0.40-0.50 mm, a positive electrode current collector is an aluminum foil with the diameter of 12-13 [mu]m, a negative electrode current collector is a copper foil with the diameter of 4.5 [mu]m, a diaphragm is a 7 + 2C + 2P ceramic gluing diaphragm, a conductive binder is used for replacing a positive electrode, the addition amount is 1.0-2.0%, and the weight ratio of a positive electrode active material to a positive electrode dressing is greater than or equal to 98%. According to the invention, the energy density of the battery is greatly improved and reaches 200Wh / kg.

The invention discloses an oxide passivation contact solar cell and a preparation method thereof. The cell has the following structure from top to bottom: Ag / ITO / NiOx:Mg / SiOx / n-c-Si / SiOx / TiOx / Ag. Thepreparation method comprises the following steps of putting a cleaned silicon wafer into a HNO3 solution for thermal oxidation growth, growing a magnesium-doped nickel oxide thin film by utilizing a magnetron sputtering method, and growing a titanium oxide thin film by a magnetron sputtering method; dividing the silicon wafer into a sample with the area of 1.5*1.5cm2 by utilizing a laser scribingtechnology, and then growing an ITO transparent conductive thin film and a metal silver electrode by a magnetron sputtering method; and naturally cooling the manufactured cell to room temperature after annealing. The method does not need expensive thin film deposition equipment such as plasma chemical vapor deposition (PECVD) or atomic layer deposition (ALD), and has the characteristics of simpleprocess, low cost, environmental friendliness and the like.

The invention relates to the field of battery material preparation methods, and discloses a preparation method of carbon-coated nitrogen-magnesium-doped porous silicon-based composite material and a lithium ion battery. The method comprises the steps of dropwise adding a carbon source solution into nano silicon dioxide powder, and carrying out high-temperature carbonization operation in a nitrogenatmosphere so as to obtain a carbon-coated nitrogen-doped silicon dioxide material; performing high-temperature reduction operation on the carbon-coated nitrogen-doped silicon dioxide material in a reducing atmosphere to obtain a carbon-coated nitrogen-doped silicon-based composite material; etching the carbon-coated nitrogen-doped silicon-based composite material to obtain a carbon-coated nitrogen-doped porous silicon-based composite material; carrying out ultrasonic dispersion operation on the carbon-coated nitrogen-doped porous silicon-based composite material to obtain a dispersed mixed turbid solution; and adding the dispersed mixed turbid solution into a magnesium source mixed solution, and carrying out separation, washing and drying operations to obtain the carbon-coated nitrogen-magnesium-doped porous silicon-based composite material. According to the method, volume expansion of silicon can be effectively inhibited, and the conductivity and the initial efficiency of the silicon-carbon material are effectively improved.

The invention discloses a three-dimensional porous titanium-based magnesium-doping coating and a preparing method thereof. Porous treatment is conducted on the surface of pure titanium or a titanium alloy matrix, and then the three-dimensional porous titanium-based magnesium-doping coating is formed through bioactive glass modification. The prepared three-dimensional porous titanium-based magnesium-doping coating has the advantages that elasticity modulus is close to that of hard bone tissue, bonding strength is high, chemical property is stable, the porous structure and bone induction elements are obtained, and new bone growth and combination are facilitated. In-situ generation of the porous structure is achieved on the surface of the surface of titanium or the titanium alloy matrix, and the pore size can be adjusted by adjusting electrolyte constitutes, concentration and technological conditions; pulse deposition of a magnesium-doping bioactive glass coating is conducted on the titanium-based porous structure, the deposition technique and target constituents are changed, and the microstructure and thickness of the coating and the content of magnesium in the coating are made controllable and adjustable. The preparing process is simple and quick, operation is convenient and controllable, and application and popularization are easy.

The invention discloses a nickel-cobalt-manganese precursor for a doped lithium ion battery. The precursor is a radial metal hydroxide, the chemical expression of the precursor is Ni0.7Co0.1Mn0.2-xMgx(OH)2, and the x is greater than or equal to 0.02 and less than or equal to 0.04. The invention also discloses a preparation method of the nickel-cobalt-manganese precursor. According to the preparation method, an Mg doping element is directly added in the coprecipitation process, so that the doping element can be uniformly distributed in precursor particles, the modification effect of the dopingelement is effectively exerted, and magnesium doping is beneficial to forming a good layered structure, enhancing the structural stability of the material and improving the cycle performance of the high-nickel ternary material.

The invention relates to a preparation method of quantum dots of titanium dioxide doped with holmium, ytterbium and magnesium. The method comprises the steps of (1) preparing a titanium dioxide precursor, and (2) preparing quantum dots, adding Ho(NO3)3-5H2O, Yb(NO3) 3-5H2O and Mg(NO3)2-6H2O into a titanium dioxide precursor solution to obtain a mixed solution C and drying and annealing the mixed solution C to obtain the quantum dots of titanium dioxide doped with holmium, ytterbium and magnesium. The quantum dots of titanium dioxide doped with holmium, ytterbium and magnesium can be used as anelectron transporting material applied in the preparation of the perovskite battery, the prepared perovskite battery can convert near-infrared light into visible light, and the conversion efficiencyis high.

The invention discloses preparation of a concentration gradient magnesium-doped lithium-rich manganese-based oxide and application of the concentration gradient magnesium-doped lithium-rich manganese-based oxide to a lithium battery, the chemical formula of the oxide is Li1.2-2x Mn0.54Ni0.13Co0.13MgxO2, and x is more than 0 and less than or equal to 0.07. the preparation method specifically comprises the following steps: (1) firstly, preparing a manganese salt, cobalt salt, nickel salt and transition metal salt mixed solution and an ammonia water and sodium carbonate mixed solution as a complexing agent and a precipitating agent according to a proportion, and injecting a magnesium salt solution into the transition metal salt mixed solution by utilizing a peristaltic pump; then adding the transition metal salt solution, a precipitator and a complexing agent into a reaction kettle through parallel flow to carry out a co-precipitation reaction to obtain precursor powder with elements distributed in a gradient manner; and (2) mixing and calcining the precursor powder and a lithium salt to obtain the concentration gradient magnesium-doped lithium-rich manganese-based positive electrode material. The gradient doping material is applied to the field of lithium batteries, and is high in discharge capacity and good in cycle performance. The preparation method disclosed by the invention is low in cost, the process has good compatibility with existing equipment, the potential of quantitative production is achieved, and relatively high industrialization value and wide application prospects are shown.

A method to fabricate boron nitride nanotubes incorporating magnesium diboride in their structure. In a first embodiment, magnesium wire is introduced into a reaction feed bundle during a BNNT fabrication process. In a second embodiment, magnesium in powder form is mixed into a nitrogen gas flow during the BNNT fabrication process. MgB2 yarn may be used for superconducting applications and, in that capacity, has considerably less susceptibility to stress and has considerably better thermal conductivity than these conventional materials when compared to both conventional low and high temperature superconducting materials.

A method of growing a p-type nitride semiconductor material having magnesium as a p-type dopant by molecular beam epitaxy (MBE), comprises supplying ammonia gas, gallium and magnesium to an MBE growth chamber containing a substrate so as to grow a p-type nitride semiconductor material over the substrate. Magnesium is supplied to the growth chamber at a beam equivalent pressure of at least 1 10-9 mbar, and preferably in the range from 1 10-9 mbar to 1 10-7 mbar during the growth process. This provides p-type GaN that has a high concentration of free charge carriers and eliminates the need to activate the magnesium dopant atoms by annealing or irradiating the material.

One or more embodiments of the present specification provide a perovskite solar cell comprising, in order from bottom to top, a substrate on which transparent conductive glass is deposited, a magnesium-doped titanium dioxide electron transport layer, a perovskite absorption layer, a hole transport layer, and an electrode, the Mg element is used as an effective doping agent to be introduced into acompact TiO2 electron transport layer in a simple mode, and the planar perovskite solar cell is constructed. Mg doping can enable the Fermi level of TiO2 to move upwards, increase the free carrier concentration of the film and reduce the defect state concentration of the deep energy level. Therefore, the resistance of TiO2 is reduced, and the fill factor and the photoelectric conversion efficiencyof the whole cell device are improved.

The invention discloses a magnesium-doped metal-organic frame DMMg0.5Co0.5F single-crystal material and a preparation method thereof. The magnesium-doped metal-organic frame DMMg0.5Co0.5F single-crystal material is composed of a DMMg0.5Co0.5F single crystal with the size of 2.0*2.0*1.0-2.5*2.5*1.5 mm<3>, wherein the mol ratio of a magnesium ion to a cobalt ion in the compound is 1:1. The used reagent is a business product and is not prepared through a tedious preparation; a novel metal-organic frame single-crystal material and a large single crystal can be obtained through the combination of a hydrothermal method and a liquid phase method; and the process is strong in controllability and easy to operate and the purity of the obtained product is high. The magnesium-doped DMCoF single-crystal material obtained from the invention is expected to be widely used in a novel metal-organic frame semiconductor, information storage and an optical apparatus.

The invention discloses a magnesium doped metal-organic framework DMMg0.5Mn0.5F single crystal material and a preparation method thereof. The magnesium doped metal-organic framework DMMg0.5Mn0.5F single crystal material is composed of DMMg0.5Mn0.5F single crystals with a size of 1.5*1.5*1.5-2.0*2.0*2.0mm<3>, and the mole percentage of magnesium ions to manganese ions in the compound is 1:1. The used reagents are commercial products and have no need for tedious preparation, hydrothermal method and liquid phase method are combined to obtain the novel metal-organic framework single crystal material and larger size signal crystals, the process has strong controllability and is easy to operate, and the prepared product has high purity. The magnesium doped DMMnF single crystal material obtained in the invention is expected to be widely used in novel metal-organic framework semiconductors, information storage and optical devices.

The invention discloses a copper nitride thin-film solar cell and a preparation method thereof. The cell comprises the following structures from bottom to top: ITO glass, a magnesium-doped copper nitride film, a component gradient copper nitride film, a selenium-doped copper nitride film, an ITO film and a silver electrode, and in the component gradient copper nitride film, the nitrogen content isgradually increased from bottom to top. The copper nitride film is prepared by using a reactive magnetron sputtering method, and the copper nitride film with gradually changed forbidden band width isobtained by adjusting the flow of reaction gas (nitrogen), so that a spectral range of sunlight absorption of the film is widened.

The invention provides a preparation method of a Ga2O3 film, which comprises the following steps of by using an organic gallium compound as a gallium source and high-purity oxygen as an oxygen source,carrying out deposition on the surface of a substrate by using a metal organic chemical vapor deposition method, and cooling to obtain the Ga2O3 film, and intermittently supplementing an organic magnesium compound in the growth process of the Ga2O3 film. The invention also provides the Ga2O3 film prepared by the preparation method. The Ga2O3 film is doped with a trace amount of magnesium. By controlling the introduction time and introduction duration of the organic magnesium compound in the preparation of the Ga2O3 film, the preparation of the trace magnesium doped Ga2O3 film is realized, anda convenient and effective means is provided for realizing a high-performance solar blind ultraviolet light detector.

The invention relates to a preparing method for a magnesium-containing hydroxyapatite coating on the surface of a carbon / carbon composite. The method comprises the steps of material pretreatment, magnesium doping treatment and water heat treatment. The preparing method has the advantages that the preparing method for the magnesium-containing hydroxyapatite coating is simple and easy to operate, the binding force of the coating is high, the coating is even, and the magnesium-containing hydroxyapatite coating has a bone tissue regeneration inducing function and sclerotin growth adjusting and remodeling functions.

The invention discloses doped and coated composite modified lithium cobalt oxide LCMO@BT and a preparation method and application thereof. The method comprises: ball-milling and uniformly mixing a magnesium compound, a cobalt compound and a lithium salt; and presintering the mixture, calcining at high temperature, and cooling to obtain the magnesium-doped lithium cobalt oxide; then adding barium salt into the weak acid aqueous solution, and heating and stirring until the barium salt is dissolved; and sequentially adding titanate and magnesium-doped lithium cobalt oxide, heating, uniformly stirring, standing for layering, pouring out supernate, drying and carrying out vacuum drying; and calcining the mixture at a high temperature, and cooling to obtain a product LCMOS@BT which can be used as an ultrahigh-voltage lithium cobalt oxide positive electrode material of a lithium ion battery. The method provided by the invention has the advantages of cheap and easily available raw materials, low cost, short calcination time and high production efficiency, is very easily used for large-scale industrial production, and has wide application prospects.

The invention relates to the technical field of photoelectric materials, and discloses a magnesium-doped zinc oxide magnetron sputtering target material and a preparation method thereof. The preparation method comprises the steps that 1, zinc oxide powder is doped with magnesium oxide powder and third oxide powder, and then the mixed powder and an ethanol solution are mixed so as to form slurry; (2) ball milling is carried out on the slurry, and then drying and sieving are carried out so as to obtain powder for molding; (3) isostatic cool pressing is carried out on the powder so as to form a green body; and (4) the green body is slowly heated to 900-1150 DEG C, heat preservation is carried out for 30-90 minutes, then the green body is quickly heated to the sintering temperature of 1300-1450 DEG C, heat preservation is carried out for 120-480 minutes, slow cooling is carried out so as to form a semi-finished product, and cutting and polishing are carried out so to obtain the magnesium-doped zinc oxide magnetron sputtering target material. The target material has the advantages that the density is high, the relative density is greater than 95% or above, meanwhile, the electrical resistivity is low and can reach 4*10<-2>, the resistance of the target material is far lower than the resistance of a target material in the prior art, the conductive effect is good, and the requirement for medium-frequency rapid sputtering of a coating production line can be met.

The invention relates to the technical field of electrode materials of lithium ion batteries, and provides a preparation method for magnesium-doped cobalt liquid. The preparation method comprises the following steps: carrying out extraction treatment on a cobalt-containing water phase treated by a P507 organic phase and a P204 organic phase to obtain a first P507 organic phase containing cobalt and magnesium, carrying out first reverse magnesium extraction treatment on the first P507 organic phase to remove most of impurity magnesium in the first P507 organic phase and to obtain a second P507 organic phase containing cobalt and the remaining part of magnesium, performing reverse magnesium extraction treatment on the remaining part of magnesium in the second P507 organic phase, and then performing reverse cobalt extraction treatment on the second P507 organic phase to obtain magnesium-doped cobalt liquid doped with different magnesium. The magnesium-doped cobalt liquid provided by the invention can be used as a raw material of a nickel-cobalt-manganese ternary precursor, and nickel-cobalt-manganese ternary precursors with different magnesium doping amounts can be prepared, so impurity magnesium in cobalt ore can be effectively utilized in a production process, and production cost is saved.

The invention provides a modified lithium ferric manganese phosphate material, and a preparation method and application thereof. The modified lithium iron manganese phosphate material comprises a magnesium-doped lithium iron manganese phosphate nuclear layer and a boron-containing coating layer coating the surface of the magnesium-doped lithium iron manganese phosphate nuclear layer. The modified lithium iron manganese phosphate material comprises a magnesium-doped lithium iron manganese phosphate nuclear layer and a boron-containing coating layer coating the surface of the magnesium-doped lithium iron manganese phosphate nuclear layer. Based on the structure, the material is higher in conductivity and lithium ion diffusivity, lower in charge transfer impedance and better in stability. When the composite material is used as a positive electrode material of a lithium ion battery, the rate capability of the battery is better, the first charge-discharge efficiency and capacity are higher, the cycle performance is better, and especially the cycle life is longer.