33results about How to "Increase defect concentration" patented technology

The invention relates to a heat insulating layer on a metallic substrate for using for high temperatures, especially for temperatures above 1300° C. Starting with a base of La2Zr2O7, the properties of the heat insulating substance to be used as the heat insulating layer are regularly improved, by substituting lanthanum cations with ions of elements Nd, Eu, Dy, Sm and/or Gd. An additional, at least partial substitution of the zirconium cations by Ce, Hf or Ta is advantageous. Improving the properties results especially in a high thermal coefficient of dilation alpha and low heat conductivity lambda.

The invention relates to a process for preparing ZrB2-SiC-ZrC complex phase ceramic materials, which is characterized in that purity of zirconium powder is not less than 98%, silicon powder and boron carbide powder are used as raw materials, batching according to reaction equation (2+x)Zr+(1-x)Si+B4C=2ZrB2+(1-x)SiC+ZrC, 0<=x<=0.5 of generating ZrB2-SiC-ZrC, then, materials containing different components are obtained. The raw materials after being ball ground and dried are sintered with heat pressing between 1500-1700DEG C by adjusting sintering technique parameter and employing self-propagating reaction of the raw materials generated in the process of heating up, thereby obtaining the ZrB2-SiC-ZrC complex phase ceramic materials of different components. Relative density of the materials prepared by the invention is larger than 97%, bending strength is 600-900MPa, fracture toughness property is 4.5-6MPa,m1/2, and hardness is 16-19GPa.

The invention relates to an avalanche diode that can be employed as an ESD protection device. An avalanche ignition region is formed at the p-n junction of the diode and includes an enhanced defect concentration level to provide rapid onset of avalanche current. The avalanche ignition region is preferably formed wider than the diode depletion zone, and is preferably created by placement, preferably by ion implantation, of an atomic specie different from that of the principal device structure. The doping concentration of the placed atomic specie should be sufficiently high to ensure substantially immediate onset of avalanche current when the diode breakdown voltage is exceeded. The new atomic specie preferably comprises argon or nitrogen, but other atomic species can be employed. However, other means of increasing a defect concentration level in the diode depletion zone, such as an altered annealing program, are also contemplated.

The invention belongs to the field of nano materials, the invention discloses a preparation method of a 2D porous TiO2 nanosheet photocatalyst rich in surface defects. The preparation method comprisesthe following steps: preparing graphene oxide by a Hummers method, preparing GO@Ti (OH) 4 by an oil bath method, preparing a 2D porous TiO2 nanosheet by calcining, and further preparing the 2D porousTiO2 nanosheet rich in surface defects by hydrogen reduction. Through cooperation of the 2D porous TiO2 nanosheet and defect engineering, active sites and edge sites of the nano photocatalyst are fully exposed, the recombination rate of photo-induced electron holes is reduced, the sunlight utilization rate is increased, and then the photocatalytic performance of the nano photocatalyst is improved. The material can be used for photocatalytic decomposition of water to produce hydrogen, which is of great significance to the development of clean energy.

The invention discloses a high-gain solar blind ultraviolet light detector based on a (GaY)2O3 amorphous film and a preparation method of the high-gain solar blind ultraviolet light detector. The detector sequentially comprises a c-plane sapphire, an active layer and a pair of parallel electrodes from bottom to top, wherein the active layer is the amorphous (GaY)2O3 film. According to the invention, Y3+ ions are used for partially replacing Ga3+ ions in Ga2O3, so that the band gap of Ga2O3 is increased, and the thin film is converted into amorphous from single crystal. The amorphous (GaY)2O3 film with a higher band gap can effectively reduce the dark current of the device, and enables the cut-off wavelength to be blue-shifted to be within 280nm. Meanwhile, the amorphous (GaY)2O3 film has higher defect concentration, and the defects not only can improve the gain, but also can be used as a recombination center to promote carrier recombination, so that compared with a pure Ga2O3 device, an amorphous (GaY)2O3 device has the advantages that the responsivity is obviously improved, the relaxation time is obviously shortened, and the detection capability on deep ultraviolet light is greatly improved.

The invention discloses a rare-earth element samarium-doped modified lithium ion battery anode material and a preparation method thereof. The method comprises the following steps of: mixing a lithium source compound, a phosphor source compound, an iron source compound, a crystalline-phase element samarium-doped compound and a carbon source compound, heating at 250-400 DEG C for 5-20h, cooling and grinding to obtain a reaction precursor; and calcining the reaction precursor at 500-800 DEG C for 10-40h, cooling to obtain an LiFe1-xSmxPO4-SmPO4/C (x=0.01-0.04) composite rare-earth element samarium-doped modified lithium ion battery anode material. The invention can effectively control the structure and the grain diameter of the composite doped modified cathode material, improve the electronic conductivity of the material and the dispersion rate of lithium ions as well as the electrochemical performance of the material, also simplify the synthesis process of the material and be convenient for industrial mass production.

The invention discloses a preparation method for a memory cell of a resistive random access memory. The method includes: step 1, a conductive film as a first electrode is formed on the surface of a substrate; step 2, a ZnO film through argon plasma bombardment treatment as an intermediate layer is prepared on the surface of the first electrode obtained by the step 1; step 3, a conductive film as a second electrode is prepared on the surface of the intermediate layer obtained by the step 2; and step 4, an isolation device is prepared on the structural basis obtained by the step 3, and the memory cell of the resistive random access memory is obtained. According to the preparation method for the memory cell of the resistive random access memory, the argon plasma bombardment treatment of the ZnO film as the intermediate medium layer is performed so that the flatness of the surface of the ZnO film is greatly improved; and the ZnO film through argon plasma bombardment treatment serves as the memory prepared by the intermediate layer, the initial presentation is the low-resistance state, the wiping of all the devices does not need the process of electric forming, and the wiping voltage is low.

The invention discloses a method for improving electrochemical performance of a lithium battery positive electrode coating material; the method for preparing the lithium battery positive electrode coating material comprises the following steps of weighing a certain amount of metal salt and/or alkali formed by metal ions and hydroxyl ions, and mixing the metal salt and/or alkali into a certain amount of low-carbon alcohol, and carrying out heating and dissolving to obtain a solution A; under the condition of mechanical stirring, adding a precipitant into the solution A, so that mixed latex is obtained; enabling the mixed sol obtained in the step (2) to be continuously stirred to obtain oxide sol; weighing a certain amount of positive electrode material powder, adding into the oxide sol obtained in the step (3), mixing under the mechanical stirring condition and standing, and washing the lower-layer precipitate, and drying to obtain the oxide coating-coated positive electrode material powder; and mixing the positive electrode material powder with a strong reducing agent, putting into a furnace, and carrying out heating and cooling to obtain a final product.

The invention relates to a near-infrared high-afterglow material and a preparation method thereof and aims to solve the technical problem that existing near-infrared long-afterglow materials are weak in afterglow intensity and short in afterglow time. A molecular formula of the near-infrared high-afterglow material is (Zn1-xCax)3(Ga0.995Cr0.005)2G22O10, wherein x is greater than or equal to 0.01 and smaller than or equal to 0.03. The preparation method includes: well mixing zinc oxide, calcium oxide, gallium oxide, chromium oxide and germanium oxide according to a chemical dosage ratio, adding a mixture into water, boiling the water, and adding nitric acid to dissolve the oxides to obtain a solution; mixing the solution with a mixed solution of water, alcohol and oleic acid to obtain a mixed solution, and performing hydrothermal reaction to obtain a solid-phase product; subjecting the solid-phase product to pre-sintering and high-temperature sintering to obtain the near-infrared high-afterglow material. The near-infrared high-afterglow material can be used in the technical field of bioluminescent imaging.

The invention provides a preparation method of a defect-rich metal oxide (sulfide)/graphene oxide composite material. A metallic lithium sheet, a graphene oxide sol and a selected oxide or sulfide are uniformly stirred in a liquid phase, and the obtained mixture is washed and dried to obtain the composite material having a certain defect concentration. The stirring step of the method is carried out in an anoxic and anhydrous environment, and excess hydrochloric acid is added after a sufficient reaction in order to remove the remaining lithium sheet. The material prepared in the invention has a large number of surface defects, so photochemical and electrochemical reactions can be easily promoted; and compounding of metal oxide (sulfide) with the graphene oxide can greatly expand the light absorption range, increase the specific surface area and improve the conductivity, so the photochemical and electrochemical properties of the oxide (sulfide) material are improved. The method is carried out at room temperature, has the advantages of simplicity in operation, and low cost, and provides a new idea for the preparation of photocatalysts and energy storage materials.

Methods for tailoring an oxygen defect concentration, such as oxygen vacancies, in a transition metal oxide and the resulting materials are provided. An epitaxial strain, such as in the form of a biaxial tensile strain of up to 5%, is applied to the transition metal oxide to increase the oxygen defect concentration in the transition metal oxide to result in a product comprising the transition metal oxide having an increased oxygen defect concentration.

The invention provides a fuel-cell catalyst doping with a porous diamond carrier and a preparation method. A flaky metal electrode material is used as a substrate; an arc plasma is used for depositinga diamond film on a surface layer; a used gas source is hydrogen, argon and methane; a mixed gas of the hydrogen and the methane is sprayed through a nozzle in a plasma muzzle; the argon and a gas-state/steam-state doping source is sprayed through a nozzle outside the muzzle by loading nano platinum/tin alloy powder, and a composite material doping with porous diamond/alloy is formed on the surface layer of the substrate. According to the fuel-cell catalyst doping with the porous diamond carrier and a preparation method provided by the invention, the porous nano diamond is used as a carrier for coating the nano alloy, and the porous nano diamond is used as the carrier so as to have high oxidation resistance and good active metal dipersibility, so that the stability of the catalyst is improved, and the defect that the catalytic activity of the catalyst is further reduced since the active metal dipersibility cannot be controlled when current nano diamond particles are used as the carrier is further overcome.

A piezoelectric component has at least one piezoelectric ceramic layer and at least one electrode adjacent the piezoelectric ceramic layer. The piezoelectric ceramic layer has a piezoelectric ceramic material of the general formula Pb_{1-x-y-[(2a-b)/2]-p/2}V_{[(2a-b)/2-p/2]}″Cu_pBa_xSr_y[(Ti_zZr_1-z)_1-a-bW_aRE_b]O₃, where 0≦x≦0.035, 0≦y≦0.025, 0.42≦z≦0.5, 0.0045≦a≦0.009, 0.009≦b≦0.011, 2a>b, p≦2a-b, RE is a rare earth metal, and V″ is a Pb vacancy.

The invention provides an antibacterial edge band and a preparation method and application thereof.The method includes the steps that PVC resin, a lubricant, auxiliaries, toner and a nano magnesium-based active factor antibacterial material are evenly mixed in a powdering machine, colloidal particles are prepared through a parallel twin-screw granulator, and the addition amount of the nano magnesium-based active factor antibacterial material is 0.5-1%; and extruding and molding the colloidal particles by a conical double-screw extruder at 160-170 DEG C, pressing textures, and printing to obtain the antibacterial edge band. The prepared nano magnesium-based active factor antibacterial material for the antibacterial edge band is small in mixing amount, uniform, low in cost and excellent in antibacterial effect, and the performance of the edge band is not affected.