33 results about "Vanadium(IV) oxide" patented technology

The invention relates to carbon-coated vanadium dioxide nanoparticles and a preparation method thereof. The particles consist of rutile-phase nano vanadium dioxide kernels and carbon shells covering the rutile-phase nano vanadium dioxide kernels, wherein the rutile-phase nano vanadium dioxide kernels are approximately square nanoparticles with a length-diameter ratio of being less than 3 and a three-dimensional size of being less than 100 nm; the thickness of the carbon shells are 1-10 nm; the carbon shells account for less than 20 percent by weight of the mass fraction of the particles. The preparation method comprises the following steps: synthesizing the rutile-phase vanadium dioxide nanopowder by using hydrothermal reaction; adding a carbon source into hydrothermal reaction liquid; then performing hydrothermal reaction to perform in-situ carbon coating. The carbon-coated vanadium dioxide nanopowder has superior thermochromic performance, good stability, low cost and high yield and is suitable for large-scale production. The nanopowder can be widely applied to energy-saving coatings, flexible energy-saving films or energy-saving glass of buildings and automobiles.

The invention provides a preparation method for a vanadium oxide composite electrode material used for a zinc ion battery. The preparation method for the vanadium oxide composite material comprises the following steps: dissolving ammonium metavanadate with water, then adding a carbon material, carrying out mixing under stirring and then carrying out drying; and subjecting a solid obtained after drying to high-temperature calcination under the protection of inert gas so as to obtain the vanadium oxide composite material. According to the invention, a variety of carbon materials can be used, and different vanadium oxide/carbon composites can be obtained by regulating calcining temperatures and time; and the vanadium oxide may have different structures and crystal forms, or may be a mixture of two or more vanadium oxides with different structures and crystal forms. When used as a positive electrode material for an aqueous zinc ion battery, the vanadium oxide composite material provided by the invention has the advantages of high specific capacity and energy density, excellent cycle stability, etc.; and a zinc ion battery based on the vanadium oxide/carbon composite positive electrode material has good application prospects in fields like green energy, portable electronic devices and communication technology.

The invention discloses an electro-optic modulator based on a Si-VO2 composite waveguide. The modulator comprises a silicon substrate, a SiO2 lower cladding, a ridge waveguide, a SiO2 upper cladding, and a metal electrode layer. The ridge waveguide is carved with a slot. A protruding strip is filled with VO2 to form the Si-VO2 composite waveguide. A flat board on two sides is filled with SiO2 for insulation. A P-type lightly doped region and an N-type lightly doped region on two sides of the slot form a PN junction. Metal electrodes are connected with heavily doped regions on two sides of the flat board. The modulator uses phase changes of ViO2 under the force of electric field to induce changes of refraction rate so as to achieve modulation. The modulator is simple in structure, high in modulation extinction ratio, and low in insertion loss. Meanwhile, the inclined ViO2 slot structure is utilized to increase the length of effect and reduce the intensity of reflected light. The modulator has wide application prospect in the field of optical communication and integrated optoelectronics.

The invention provides spectrum locally-modified hot color nano-composite powder and a preparation method thereof. The powder is of a multilayer composite core-shell structure which consists of a V2O layer, a precious metal layer and a transparent oxide layer, wherein the V2O layer serves as a core layer; the precious metal layer and the transparent oxide layer are respectively positioned on the second layer or the third layer. According to the spectrum locally-modified hot color nano-composite powder and the preparation method thereof, the precious metal layer and the transparent oxide layer coat the surfaces of V2O nano-particles, so that the stability of the V2O nano-particles can be improved, the spectral characteristics of V2O nano-powder can be adjusted, and the transmission color and the reflection color of the V2O nano-powder are adjusted; therefore, the aim of improving the color of the V2O powder is fulfilled. The powder can be widely applied to the fields of heat insulation coatings, lamination and the like, can be applied to an intelligent energy-saving coating, and can also be applied to the heat insulation places of glass, outer walls and the like.

The invention relates to a preparation method of a vanadium dioxide nano material and application in a rechargeable magnesium battery. The vanadium dioxide nano material, of which the crystal structure is a phase B, is prepared by taking vanadium pentoxide, citric acid and a surfactant which are low in cost as raw materials and adopting a one-pot hydrothermal method; the vanadium dioxide nano material is high in purity and good in crystallization performance, and the preparation method is easy to control. When the phase-B vanadium dioxide nano material is used as a cathode material of the rechargeable magnesium battery, at the current density of 50 mA/g, the first specific discharge capacity can be up to 394.2 mAh/g; after the battery is cycled for 60 circles, the specific discharge capacity still can be kept at 205.9 mAh/g, and a discharge voltage platform reaches 2.1 V (vs.Mg<2+>/Mg), so that relatively high electrochemical magnesium removal and embedding performance is achieved.

The invention discloses a high-throughput simulation method for monoclinic phase vanadium dioxide material point defect forming energy. The method comprises the following steps of: S1, construction of a monoclinic phase vanadium dioxide point defect model; S2, calculation and simulation of defect forming energy; and S3, result processing and analysis. According to the method, the relationship between vanadium dioxide intrinsic point defects and oxygen partial pressure is clear, and the atomic microstructures and electronic behaviors of the intrinsic point defects are simulated through high throughput, so that significance is provided for strengthening the oxidation resistance of VO2 thin films, improving the visible light transmittance and regulating and controlling the metal insulator transformation temperature of VO2, and positive effects are provided for the practical application of intelligent windows.

The invention relates to a flexible thin film electrode material and a preparation method thereof. The electrode material adopts an ultrathin titanium sheet as a substrate, a layer of intensively arranged vanadium trioxide nanosheet array is distributed on the substrate; the surface of the vanadium trioxide nanosheet array is also coated with a layer of carbon material. The preparation method comprises the following steps: firstly, hydrothermally generating the vanadium trioxide nanosheet array on the ultrathin titanium sheet, and then conducting carbon coating by taking glucose as a carbon source to form the vanadium trioxide @ carbon compound nanosheet array, namely the flexible thin film electrode material. The electrode material can be used as a positive electrode and a negative electrode at the same time to assemble a supercapacitor. The method is simple to operate and facilitates realization of mass production, the obtained capacitor has excellent flexibility, the whole capacitor is only 40 micrometers in thickness, dissymmetrical energy storage principle, high voltage and high volume energy density are shown, and the flexible thin film electrode material can be used for the fields of flexible wearable electronic products and the like, and is hopeful to generate excellent social and economic benefits.

The invention relates to a graphene-containing vanadium dioxide composite powder and a preparation method and application thereof. The graphene-containing vanadium dioxide composite powder consists ofcore-shell particles and graphene dispersed between the core-shell particles, each core-shell particle consists of a vanadium dioxide particle and metal, the metal wraps the surface of the vanadium dioxide to form a metal shell, and the mass ratio of the vanadium dioxide particles, the metal and the graphene is (70 to 98) to (1 to 20) to (1 to 10). Through the synergistic effect of the metal shells and the graphene of the graphene-containing vanadium dioxide composite powder, the high conductivity of the graphene-containing vanadium dioxide composite powder can be achieved, and the electron transfer capability and infrared transmission and reflection capability of the graphene-containing vanadium dioxide composite powder are increased. When temperature increases, plasma resonance is generated inside the vanadium dioxide particles, a conductive network formed by the vanadium dioxide particles, the metal shells and the graphene carries out the total reflection of infrared light, at themoment, the transmission and absorption of infrared rays can be greatly reduced, consequently, temperature rise is decreased, and the objective of energy saving is achieved.

The present invention addresses the problem of providing a process for producing vanadium-dioxide-containing particles which have a small average particle diameter and a narrow particle diameter distribution, are excellent in terms of monodispersity and dispersion stability, and have excellent thermochromic properties. The process for producing vanadium-dioxide-containing particles of the presentinvention comprises using a flow-through type reactor including a hydrothermal reaction part and using a liquid reaction mixture obtained by mixing a raw-material slurry, the slurry comprising a vanadium-containing compound and water, and a compound that reacts with the vanadium-containing compound, with water in a supercritical or subcritical state. The production process is characterized in that1) the water is degassed water, 2) the time over which the liquid reaction mixture passes through the hydrothermal reaction part is 3-1,000 seconds, 3) the raw-material slurry is subjected, before the hydrothermal synthesis, to a desalting treatment for salt removal therefrom and hence the particles have an average particle diameter of 15-40 nm and an average crystallite diameter of 15-40 nm, or4) prior to the step of producing vanadium-dioxide-containing particles, the raw-material slurry is subjected to a dispersing treatment.

The invention discloses amethod for preparing an intelligent temperature-controlpolyester chip with an in-situ polymerization method. The method comprises steps as follows: Step 1, surfaces of vanadium dioxidenano-powder with the chemical composition of V1-xMxO2 are inoculated with polymerizableorganic functional groups, wherein M refers to a doped element, and x is larger than or equal to 0 and smaller than or equal to 0.5; Step 2, thevanadium dioxidenano-powder provided with the organic functional groups is uniformly dispersed in an ethylene glycol solution, uniform slurry is prepared from the ethylene glycol solution and terephthalic acid, and the polyester chip is synthesized. Thepolyester chip prepared with the method forms a film throughtwo-way stretching, can be applied to glass films and can also be produced into plates or sheets, and the prepared films or sheets are high in transparency, low in haze and high in ageing resistance. Thepolyester chip is widely applied and can be applied to glass, wall surfaces and transportation means such as vehicles, ships and the like to control incoming and outgoing of infrared rays and heat energy to achieve an intelligent temperature-control purpose.

The invention discloses a VO2-Sb film material with high speed and high data retention, and a preparation method thereof. The material is characterized in that a chemical structural formula of the material is (VO2)xSb100-x, wherein the atomic number percentage content x of VO2 is greater than 0 and less than 30. The preparation method comprises the following specific steps: high-purity Sb and VO2are adopted as target materials; a magnetron sputtering device is adopted; a double-target co-sputtering method is adopted; high-purity argon is used as working gas; a quartz wafer or a silicon waferis adopted as a substrate material for surface deposition; the direct-current sputtering power of the Sb target is adjusted to be 14-18W; the radio-frequency sputtering power of the Sb target is adjusted to be 30-35W; sputter coating is carried out at the room temperature to obtain the VO2-Sb film material for a phase change memory. The film material has the advantages of relatively high crystallization temperature and data retention, relatively high crystallization speed, relatively large amorphous-state/crystalline-state resistance ratio and relatively high thermal stability.

The invention discloses novel vanadium oxide anode material preparation through valency regulation and surface modification and provides a modified vanadium oxide electrode material preparation method. The method uses a vapor deposition method to deposit phosphate on the vanadium oxide surface with an inert gas as a carrier gas to obtain a modified vanadium oxide electrode material. According to the modified vanadium oxide, low-valency vanadium ions and phosphate are introduced, the electrochemical surface area is also increased, active sites are increased, the lithium ion diffusion rate is increased, the diffusion channel is shortened, the capacitive performance and the cycle stability of nickel sulfide can be effectively improved, and great application prospect exists in the aspect of energy storage.

The invention discloses a mixed transition metal borate negative electrode material and a preparation method thereof. Mixed transition metal borate comprises two transition metal elements, namely ironand vanadium, and has a chemical formula of FeVBO4 or FeVBO4/C, wherein the FeVBO4 belongs to a monoclinal system; and cell parameters are as follows: a is equal to 9.4-9.9angstrom, b is equal to 3.0-3.5angstrom, c is 9.1-9.6angstrom, beta is equal to 90-93 degrees and Z is equal to 4. The preparation method comprises the following steps of taking a vanadium salt or vanadium oxide, an iron salt or iron oxide, boric acid or boron oxide or borate and citric acid or glucose or other organic carbon materials as raw materials; mixing by using a sol-gel method; carrying out presintering and curing;and finally sintering to obtain the mixed transition metal borate negative electrode material. The mixed transition metal borate is used as a negative electrode material for a lithium-ion battery, the discharge voltage plateau to lithium is about 0.6V (vs. Li), formation of lithium dendrites can be effectively avoided and the safety performance of the lithium-ion battery is improved.

The invention provides a preparation method of a wafer-level vanadium dioxide film. The preparation method comprises the following steps of S1, providing a metal vanadium film with uniform growth; andS2, under the condition that the temperature is 450-650 DEG C and oxygen-free, oxidizing the metal vanadium film by using water vapor to obtain a monoclinic phase vanadium dioxide film. The preparation method can be used for preparing the vanadium dioxide thin film with the excellent performance of the wafer level size, is uniform and compact, and can achieve the resistance change of three to four orders of magnitudes in the phase change process. According to the preparation method, the water vapor is used as a mild oxidizing agent, a self-adjusting oxidation mechanism can be realized in thegrowth process when the vanadium dioxide film is prepared, so that a stable positive tetravalent monoclinic phase vanadium dioxide film can be prepared. According to the preparation method, the growthtemperature zone prepared by the vanadium dioxide film is greatly expanded, and the vanadium dioxide film can be efficiently prepared within the range of 450-650 DEG C; and the method is simple and easy to implement and high in repeatability, and the whole film growth process is non-toxic, environment-friendly and low in cost.