2691 results about "Oxide composite" patented technology

A silicon-silicon oxide-lithium composite comprises a silicon-silicon oxide composite having such a structure that silicon grains having a size of 0.5-50 nm are dispersed in silicon oxide, the silicon-silicon oxide composite being doped with lithium. Using the silicon-silicon oxide-lithium composite as a negative electrode material, a lithium ion secondary cell having a high initial efficiency and improved cycle performance can be constructed.

The invention belongs to the fields of material synthesis and energy technology, and especially relates to a graphene/metal oxide composite cathode material for lithium ion batteries and a preparation method thereof. Grapheme is dispersed into various metal oxide precursor salt solutions; a graphene/metal oxide compound is obtained directly by a hydrothermal method, or an graphene/metal oxide compound is obtained by a liquid in-situ polymerization method or a coprecipitation process; and the graphene/metal oxide compound is obtained by heat treatment or hydrothermal treatment. In the invention, the novel three-dimensional composite cathode material of graphene-coated metal oxide or graphene-anchored metal oxide is prepared by carrying metal oxide particles with graphene as a carrier. The obtained composite material can be used as a lithium ion battery cathode, which has a high specific capacity, excellent cycle stability and rate capability, and is expected to be used as a lithium ion battery cathode material with a high energy density and a high power density.

A high permittivity gate dielectric is used in an NROM memory cell. The gate dielectric has a dielectric constant greater than silicon dioxide and is comprised of an atomic layer deposited and/or evaporated nanolaminate structure. The NROM memory cell has a substrate with doped source/drain regions. The high-k gate dielectric is formed above the substrate between a pair of the source/drain regions. A polysilicon control gate is formed on top of the gate dielectric. The gate dielectric can have an oxide-high-k dielectric-oxide composite structure, an oxide-nitride-high-k dielectric composite structure, or a high-k dielectric-high-k dielectric-high-k dielectric composite structure.

The present invention is a method for manufacturing a negative electrode material for a secondary battery with a non-aqueous electrolyte comprising at least: coating a surface of powder with carbon at a coating amount of 1 to 40 mass % with respect to an amount of the powder by heat CVD treatment under an organic gas and/or vapor atmosphere at a temperature between 800° C. and 1300° C., the powder being composed of at least one of silicon oxide represented by a general formula of SiO_x (x=0.5 to 1.6) and a silicon-silicon oxide composite having a structure that silicon particles having a size of 50 nm or less are dispersed to silicon oxide in an atomic order and/or a crystallite state, the silicon-silicon oxide composite having a Si/O molar ratio of 1/0.5 to 1/1.6; blending lithium hydride and/or lithium aluminum hydride with the powder coated with carbon; and thereafter heating the powder coated with carbon at a temperature between 200° C. and 800° C. to be doped with lithium at a doping amount of 0.1 to 20 mass % with respect to an amount of the powder. As a result, there is provided a method for manufacturing a negative electrode material for a secondary battery with a non-aqueous electrolyte that enables a silicon oxide negative electrode material superior in first efficiency and cycle durability to conventional ones to be mass-produced (manufactured) readily and safely even in an industrial scale.

The invention relates to a method for preparing continuous graphen/zinc oxide composite structure in large area, which belongs to the preparation field of the novel nanometer material, and is applicable to the fields such as sensor, solar panel, novel nanometer part and the like. The method comprises the following three steps that: first step: uniformly dispersing graphen or graphene oxide in liquid phase; second step: utilizing a hydrothermal process to ensure the zinc oxide nanometer structure and the graphen two-dimensional sheet to form a continuous structure in a three-dimensional space; third step: transferring the prepared composite structure onto a substrate to be dried. The method has simple process and low device requirement since the composite structure is synthesized in the solution; the process repeatability is strong, and the process parameter can be well controlled; the prepared graphen/zinc oxide composite structure has large area and is continuous, the generated zinc oxide nanometer sheet layer, nanometer particle and nanometer line are connected with each other and intersected with each other under the effect of the graphen so as to form a continuous porous structure in the three-dimensional space.

The invention relates to platinum-metal oxide composite particles and their use as electrocatalysts in oxygen-reducing cathodes and fuel cells. The invention particularly relates to methods for preventing the oxidation of the platinum electrocatalyst in the cathodes of fuel cells by use of these platinum-metal oxide composite particles. The invention additionally relates to methods for producing electrical energy by supplying such a fuel cell with an oxidant, such as oxygen, and a fuel source, such as hydrogen.

The invention relates to a graphene nanometer sheet-cobaltous oxide composite negative electrode material of a lithium ion battery and a preparation method thereof, and belongs to the technical field of batteries. The negative electrode material consists of graphene nanometer sheets and cobaltous oxide, wherein the graphene nanometer sheets are distributed on cobaltous oxide particles in a staggering way; the mass fraction of the graphene nanometer sheets is 5 to 90 percent; the thickness of the graphene nanometer sheets is 1 to 50 nanometers; and the particle size of the cobaltous oxide is 10 to 500 nanometers. The preparation method comprises the following steps: dispersing graphite oxide in alcohol-water solution or aqueous solution with ultrasound or stirring; adding cobalt salt, alkali and a reducing agent into the mixture and pouring the mixture into a hydrothermal kettle after stirring; performing further sealing and synchronous hydrothermal reaction, washing, filtering and drying to obtain a graphene nanometer sheet-cobaltous oxide composite; and processing the graphene nanometer sheet-cobaltous oxide composite in the protective atmosphere to obtain the graphene nanometer sheet-cobaltous oxide composite negative electrode material. In the invention, when the material is charged or discharged by a current of 200mA/g, the reversible specific capacity of the material can be stabilized in a range of over 900mAh/g.

The present invention facilitates semiconductor device operation and fabrication by providing a cap-annealing process that improves channel electron mobility without substantially degrading PMOS transistor devices. The process uses an oxide/nitride composite-cap to alter the active dopant profile across the channel regions. During an annealing process, dopants migrate out of the Si/SiO2 in a channel region thereby altering the dopant profile of the channel region. This altered profile generally improves channel mobility thereby improving transistor performance and permitting smaller density designs.

Embodiments presented herein provide a new approach for high-performance lithium-sulfur battery by using novel carbon-metal oxide-sulfur composites. The composites may be prepared by encapsulating sulfur particles in bifunctional carbon-supported metal oxide or other porous carbon-metal oxide composites. In this way, the porous carbon-metal oxide composite confines sulfur particles within its tunnels and maintain the electrical contact during cycling. Furthermore, the uniformly embedded metal oxides in the structure strongly adsorb polysulfide intermediates, avoid dissolution loss of sulfur, and ensure high coulombic efficiency as well as a long cycle life.

Metal oxide composites containing highly dispersed single-walled carbon nanotubes were prepared using sol-gel methods and shown to be electrically conducting.

The invention provides a corrosion-inhibiting anionic intercalated hydrotalcite/nano oxide composite material, a preparation method thereof and application of the corrosion-inhibiting anionic intercalated hydrotalcite/nano oxide composite material. The preparation method is as follows: corrosion-inhibiting anions are directly inserted between hydrotalcite layers by the one-step coprecipitation method and the roasting restoring method; the nano oxide is generated by means of in situ synchronization during the process of generation of hydrotalcite crystals by controlling the mixture ratio of divalent metal ions to trivalent metal ions, the pH value of a reaction solution and the reaction temperature; and the corrosion-inhibiting anionic intercalated hydrotalcite/nano oxide composite material with the anti-corrosive function is prepared. The invention is mainly characterized in that the in situ preparation method for the hydrotalcite/oxide composite material provided with a nano lamellar structure improves the release amount of a corrosion inhibitor and reduces the water absorption of a coating by leading into the corrosion inhibitor with the anti-corrosive function and the nano oxide which is generated in situ during the reaction process. The composite material can be used to be pigment of an anti-corrosive metallic coating system, and particularly has potential application value in improving the anti-corrosive performance of a magnesium alloy anti-corrosive coating.

The invention relates to a high-specific-area carbon/metallic oxide composite electrode material of a lithium battery, an electrode and preparation methods for the high-specific-area carbon/metallic oxide composite electrode material and the electrode. A metallic oxide is deposited on high-specific-area carbon powder by using an atomic layer deposition method, and the mass ratio of a metallic oxide film to high-specific-area carbon is between 70 percent and 90 percent. The invention also provides a method for preparing the high-specific-area carbon/metallic oxide composite electrode material by using the atomic layer deposition method, and a method for preparing the electrode by using the high-specific-area carbon/metallic oxide composite electrode material. The high-specific-area carbon/metallic oxide composite electrode material has a high-mass-ratio characteristic, and the lithium battery prepared from the high-specific-area carbon/metallic oxide composite electrode material has a long cycle life and high capacitance stability.

The invention belongs to the technical field of metal organic skeletal materials, and discloses a Cu-based organic skeleton-graphene oxide composite porous material and a preparation method and application thereof. The preparation method particularly comprises the following steps of uniformly mixing copper acetate, 1,3,5-benzene tricarboxylic acid and graphene oxide; carrying out ball milling; washing; centrifugalizing; and drying to obtain the Cu-based organic skeleton-graphene oxide composite porous material. The preparation method disclosed by the invention has the advantages of short reaction time (only 30 minutes), no solvent, large preparation quantity, low energy consumption, simple operation method, and the like, is a high-efficiency, clean and environment-friendly novel green synthetic method. The obtained Cu-based organic skeleton-graphene oxide composite porous material greatly increases the adsorption capacity on hydrocarbon VOCs (Volatile Organic Compounds) and achieves the purposes that the adsorption capacity on methanol is 2.06 times of the adsorption capacity on the methanol caused by a Na-ZSM molecular sieve, 2.54 times of the adsorption capacity on the methanol caused by flexible-MOF(E), and 1.79 times of the adsorption capacity on the methanol caused by HKUST-1 under the same condition.

The present invention provides a precious metal—metal oxide composite cluster, wherein said cluster is formed as a single particle by combining a precious metal portion comprising a single atom or an aggregate of a plurality of atoms consisting of one or more precious metals, and a metal oxide portion comprising a single molecule or an aggregate of a plurality of molecules consisting of one or more metal oxides, and wherein said particle has a particle size between 1 and 100 nm.

A non-oxide compound magnesite-graphite brick containing carbon less than 6% belongs to a fire resisting material. The material contains magnesia of 75-94%, carbon of 1-5%, non-oxide such as nitride and boride of 0.4-20%, additive of 0-5%, and binder containg carbon. Such magnesite-graphite brick with low carbon has a low heat conductivity, a small acierating to the molten steel and less pollution to the low carbon steel compared to the common magnesite-graphite brick. The magnesite-graphite brick has a good slag resistance because the magnesia is the primary component. And it also has a good heat shock capacity because the carbon is one of the primary components. The carbon prevents said non-oxide from being oxidated. The brick maintains a good heat and shock resistance and slag resistance when reducing the proportion of the carbon because said non-oxide has a low heat expansion and a wet resistance to the slag.

The present invention is a negative electrode material for a secondary battery with a non-aqueous electrolyte comprising at least a silicon-silicon oxide composite and a carbon coating formed on a surface of the silicon-silicon oxide composite, wherein at least the silicon-silicon oxide composite is doped with lithium, and a ratio I(SiC)/I(Si) of a peak intensity I(SiC) attributable to SiC of 2θ=35.8±0.2° to a peak intensity I(Si) attributable to Si of 2θ=28.4±0.2° satisfies a relation of I(SiC)/I(Si)≦0.03, when x-ray diffraction using Cu—Kα ray. As a result, there is provided a negative electrode material for a secondary battery with a non-aqueous electrolyte that is superior in first efficiency and cycle durability to a conventional negative electrode material.

The invention discloses a nanosilver/graphene oxide composite dispersion fluid, and a preparation method and application thereof. The dispersion fluid comprises a liquid medium and a nanosilver/graphene oxide composite, wherein the nanosilver/graphene oxide composite is uniformly dispersed in the liquid medium; the concentration of the dispersion fluid is 0.01 to 10 mg/ml; and nanosilver particles in the nanosilver/graphene oxide composite are uniformly dispersed and adhered onto the surface of graphene oxide, and the sizes of the nanosilver particles are in a range of 5 to 50 nm. According to the invention, a hypergravity rotating packed bed or a micro-channel reactor is used as reaction equipment; no reducing agent is needed in the process of preparation; and the prepared nanosilver/graphene oxide composite dispersion fluid is transparent and stable and is free of precipitates after standing for six months. Compared with the prior art, the method provided by the invention is rapid, simple, efficient and applicable to large-scale industrial production. The nanosilver/graphene oxide composite dispersion fluid provided by the invention has wide application prospects in fields like catalysis, energy storage, electronics, antibiosis and surface Raman enhancement.

A recyclable esterification or transesterification catalyst and methods for making and using the same are provided herein. The catalyst can be used to prepare biodiesel or methyl soyate from various feedstocks, including vegetable oils and animal fats. The catalyst can both esterify free fatty acids and transesterify mono-, di-, and triglycerides. The catalyst can also be combined with a metal oxide, and optionally calcined, prior to carrying out a catalytic reaction.

The invention relates to a method for preparing a lithium iron phosphate composite material for lithium cells. The products prepared by the conventional method are undesirable in carbon encapsulation uniformity and purity. The method comprises: firstly, dissolving soluble lithium compound in deionized water to prepare lithium-containing solution in which the lithium ion concentration is 0.3 to 0.9mol/L, adding graphene oxide, stirring, and after the graphene oxide is dispersed, adding phosphoric acid and ferrite to form mixed solution; secondly, filling the mixed solution in a stainless reaction kettle, reacting for 1 to 4 hours at 180 to 220 DEG C, filtering reaction liquid, washing, and drying to obtain a lithium iron phosphate/graphene oxide composite material; and finally, charging hydrogen to perform a reduction reaction to obtain the lithium iron phosphate/graphene oxide composite material. In the lithium iron phosphate/graphene oxide composite nano material obtained by the method, the composition is uniform, the conductivity of lithium iron phosphate is improved greatly, the low conductivity of the lithium iron phosphate cathode material is overcome successfully, and the capacity under large-current discharge of the cells is improved.

The invention discloses a ferroferric oxide/reduced graphene oxide composite wave-absorbing material with a hollow hemisphere structure, which is characterized in that ferroferric oxide nanoparticles with the hollow hemisphere structure are uniformly grown on the upper and lower surfaces of the reduced graphene oxide sheet to form a wave-absorbing material with a multi-layer composite structure and a nanosized thickness. The thickness of the composite wave-absorbing material is less than the range of 100 -1,000nm, which is the skin depth of ferromagnetic materials in a microwave frequency band. The invention also discloses a preparation method of the composite wave-absorbing material. The composite wave-absorbing material improves the content of ferroferric oxide in a composite material, has a thickness less than the skin depth of ferromagnetic materials in microwave frequency band, namely, 100-1,000nm, and effectively inhibits the skin dissipation of composite materials. The composite wave-absorbing material has light weight and good wave-absorbing property in actual utilization, not only can effectively absorb electromagnetic wave, but also can deflect and scatter radar waves, greatly improves the stealth effect in actual utilization, and completely meets requirements of a new wave-absorbing material of being thin, light, wide, and strong.

The invention discloses a composite material used for catalyzing and degrading nitrogen oxide and its preparation method and application thereof. The invention of the hollow g-C₃N₄ nanospheres/reduced graphene oxide composite-polymer carbonized nanofiber material is prepared as follow: 1) the preparation of silica nanospheres; 2) the preparation of hollow g-C₃N₄ nanospheres; 3) the preparation of graphene oxide; 4) the preparation of surface modified hollow g-C₃N₄ nanoparticles preparation; 5) the preparation of composites; 6) the preparation of composite-polymer carbon nanofiber material. The raw materials used in the process is low cost and easy to get; the operation of the invention is simple and convenient without the use of expensive equipment in the whole process; the composite has high adsorption efficiency of ppb level nitrogen oxide with good repeatability.

The invention discloses a silicon-carbon composite material, a preparation method of the silicon-carbon composite material, and a lithium ion battery containing the silicon-carbon composite material. The preparation method comprises the following steps of: (1) reducing silicon dioxide by using metal with activity larger than that of silicon, so as to obtain a porous silicon-metal oxide composite; (2) corroding the metal oxide by acid, so as to obtain porous silicon; and (3) coating the surface of the porous silicon by carbon by taking a carbon source as a raw material, so as to obtain the silicon-carbon composite material. The silicon in the silicon-carbon composite material is prepared through using a metallothermic reduction method and porous silicon particles prepared through using the metallothermic reduction method are micron-sized and hardly agglomerate; the pore walls and the pore diameters in the porous silicon particles are nano-sized; compared with imporous micron-sized silicon powder, for the silicon-carbon composite material, the porous silicon particles have the characteristics that a diffusion path of a lithium ion in a silicon substrate is shortened, thus being beneficial to charging and discharging with large current, the pores can hold the volume expansion of silicon during silicon intercalation and the charging and discharging cycle life of the material is prolonged. The surfaces of the porous silicon particles are coated with a carbon layer with the certain pores and the conductivity of the silicon-carbon composite material is enhanced.