2453results about "Titanium dioxide" patented technology

Nanocomposite materials comprising a metal oxide bonded to at least one graphene material. The nanocomposite materials exhibit a specific capacity of at least twice that of the metal oxide material without the graphene at a charge/discharge rate greater than about 10C.

Liquid feed flame spray pyrolysis of solutions of a metal oxide precursor which is an alkoxide or C_1-6 carboxylate and at least one second metal oxide precursor and/or second metal compound dissolved in oxygenated solvent by combustion with oxygen lead to the formation of sub-micron mixed-metal oxide powders not accessible by other processes or by the pyrolysis of metal chlorides or nitrates. The powders have numerous uses in advanced materials applications including particulate solid state lasers, advanced ceramic materials, and as catalysts in organic synthesis and automobile exhaust systems.

The process for preparing tubular titanium oxide particles comprises subjecting a water dispersion sol, which is obtained by dispersing (i) titanium oxide particles and/or (ii) titanium oxide type composite oxide particles comprising titanium oxide and an oxide other than titanium oxide in water, said particles having an average particle diameter of 2 to 100 nm, to hydrothermal treatment in the presence of an alkali metal hydroxide. After the hydrothermal treatment, reduction treatment (including nitriding treatment) may be carried out. The tubular titanium oxide particles obtained in this process are useful as catalysts, catalyst carriers, adsorbents, photocatalysts, decorative materials, optical materials and photoelectric conversion materials. Especially when the particles are used for semiconductor films for photovoltaic cells or photocatalysts, prominently excellent effects are exhibited.

Compositions that include nanoscale structured materials or precursors thereof (e.g., self-assembling peptides) are described. The compositions can include other substances (e.g., a vasoconstrictor). Also described are methods for using the compositions to promote hemostasis, to protect the skin or wounds from contamination, to decontaminate a site upon removal of previously applied compositions that provided a protective coating, and to inhibit the movement of bodily substances other than blood. The compositions are also useful in isolating tissue, removing tissue, preserving tissue (for, e.g., subsequent transplantation or reattachment), and as bulking, stabilizing or hydrating agents. Medical devices that include the compositions (e.g., a stent or catheter), bandages or other wound dressings, sutures, and kits that include the compositions are also described.

A new, cost effective process for the production of ultrafine particles which is based on mechanically activated chemical reaction of a metal compound with a suitable reagent. The process involves subjecting a mixture of a metal compound and a suitable reagent to mechanical activation to increase the chemical reactivity of the reactants and/or reaction kinetics such that a chemical reaction can occur which produces a solid nano-phase substance. Concomitantly, a by-product phase is also formed. This by-product phase is removed so that the solid nano-phase substance is left behind in the form of ultrafine particles. During mechanical activation a composite structure is formed which consists of an intimate mixture of nano-sized grains of the nano-phase substance and the reaction by-product phase. The step of removing the by-product phase, following mechanical activation, may involve subjecting the composite structure to a suitable solvent which dissolves the by-product phase, while not reacting with the solid nano-phase substance. The process according to the invention may be used to form ultrafine metal powders as well as ultrafine ceramic powders. Advantages of the process include a significant degree of control over the size and size distribution of the ultrafine particles, and over the nature of interfaces created between the solid nano-phase substance and the reaction by-product phase.

The invention relates to a method of preparing a solution containing colloidal particles which contain crystalline titanium dioxide wherein one or more hydrolysable titanium-containing compound(s) is stabilised by oxalic acid in a reaction medium. The reaction further relates to the preparation of titania materials (including particulate materials, coating solutions and films) which comprise or include anatase phase titania, and so are suitable in photocatalytic applications. The invention also deals with a method of preparing B-phase titania.

The invention provides a method for preparing a titanium dioxide nano belt, belonging to the nano material technical field. The prior methods for preparing the titanium dioxide nano belt comprise the hydro-thermal method and the combination method of the sol-gel method and the hydro-thermal method. The prior electrostatic spinning method is applied to the preparation of nano fibers. The invention comprises three steps that: 1. a spinning solution is prepared; the mixture of polymethylmethacrylate and vinylpyrrolidone is used as a macromolecule template, and the mixture of chloroform and N,N-dimethylformamide is used as a solvent; 2. a titanium alkoxide/ macromolecule template compound nano belt is prepared; the electrostatic spinning method is used, and the technical parameters are as follows: the voltage is between 15 and 25kV and the curing distance is between 15 and 30cm; 3. a TiO2 nano belt is prepared; the heat treatment method is used, and the technical parameters are as follows: the rate of temperature rise is between 0.5 and 2 DEG C/min and the heat preservation time at the temperature of between 500 and 900 DEG C is between 10 and 15h; for the TiO2 nano belt prepared, the width is between 5 and 15mu m, the thickness is between 30 and 60nm and the length is more than 200mu m; the TiO2 nano belt comprises a pure phase anatase type TiO2 nano belt and a pure phase rutile type TiO2 nano belt.

The invention discloses a method for extracting tungsten, titanium and vanadium from a waste SCR (selective catalytic reduction) catalyst, which comprises the following steps: crushing the waste SCR catalyst, adding a strongly alkaline solution, and reacting; filtering, separating, then adding strong acid into the sodium tungstate and sodium vanadate mixed solution, and reacting to obtain tungstic acid and a sodium salt and vanadic acid mixed solution; regulating the pH value of the sodium salt and vanadic acid mixed solution until precipitate is separated out, thus obtaining ammonium vanadate; then adding sulfuric acid into the tungsten-and-vanadium-removed SCR catalyst, and reacting to obtain a titanyl sulfate solution and solids such as aluminum slag and the like; then adding water into the titanyl sulfate solution, and hydrolyzing to obtain titanic acid and a waste acid solution; and finally, respectively calcining the obtained ammonium vanadate, tungstic acid and titanic acid to obtain vanadium pentoxide, tungsten trioxide and titanium dioxide. According to the invention, tungsten, titanium and vanadium can be extracted from the SCR catalyst through the reaction with strong alkali and strong acid at a low temperature, the equipment requirement is low, the energy consumption is low, some products having added values can be coproduced, and no secondary pollution is generated, thereby facilitating popularization and application.

Disclosed are porous ceramic balls with a hierarchical porous structure ranging in size from nanometers to micrometers, and preparation methods thereof. Self-assembly polymers and sol-gel reactions are used to prepare porous ceramic balls in which pores ranging in size from ones of nanometers to tens of micrometers are hierarchically interconnected to one another. This hierarchical porous structure ensures high specific surface areas and porosities for the porous ceramic balls. Further, the size and distribution of the pores can be simply controlled with hydrophobic solvent and reaction time. The pore formation through polymer self-assembly and sol-gel reactions can be applied to ceramic and transition metals. Porous structures based on bioceramic materials, such as bioactive glass, allow the formation of apatite therein and thus can be used as biomaterials of bioengineering, including bone fillers, bone reconstruction materials, bone scaffolds, etc.

The present invention relates to a method of making nanoparticulates in a flame reactor, the nanoparticulates having controlled properties such as weight average particle size, composition and morphology. The nanoparticulates made with the method of present invention may be tailored to a specific weight average particle size range, such as from about 1 nm to about 500 nm. In addition to weight average particle size, the nanoparticulates made with the method of the present invention may include a variety of materials including metals, ceramics, organic materials, and combinations thereof. Moreover, the method of the present invention allows control over the morphology of the nanoparticulates, which allows the production of nanoparticulates with any desired morphology including spheroidal and unagglomerated; and agglomerated (aggregated) into larger units of hard aggregates.

In one aspect, the process includes providing a precursor medium comprising a liquid vehicle and a precursor to a component, and flame spraying the precursor medium under conditions effective to form a population of nanoparticles, wherein the nanoparticles include the component. The population of nanoparticles, as formed, comprises less than about 5 percent by volume particles having a particle size greater than 1.0 μm. A size distribution of the population of nanoparticles may have a d50 value less than about 500 nm, and it may be unimodal. The size distribution may have a geometric standard deviation of less than about 2. The process may occur continuously for at least four hours or more. Greater than about 90 percent by weight of the precursor to the component in the precursor medium may be converted to the component in the nanoparticles. The process typically occurs in an enclosed flame spray reactor.

The invention relates to a process for decreasing flame temperature in a flame spray reaction system, the process comprising the steps of providing a precursor medium comprising a precursor to a component; flame spraying the precursor medium under conditions effective to form a population of product particles; and decreasing the flame temperature by contacting the flame with a cooling medium. The process of the present invention allows for the control of the size, composition and morphology of the nanoparticles made using the process. The invention also relates to a nozzle assembly that comprises a substantially longitudinally extending atomizing feed nozzle that comprises an atomizing medium conduit and one or more substantially longitudinally extending precursor medium feed conduits. The nozzle assembly of the present invention is used in a flame spray system to produce nanoparticles using the processes described herein.

The invention concerns a process for producing a spinel compound of formula Li4Ti5O12, comprising a step of preparing a mixture of an organo-lithium compound selected from lithium alcoholates with an organo-titanium compound selected from titanic acid esters, in a liquid medium, and a step of hydrolyzing the mixture of said compounds. The invention also concerns a Li4Ti5O12 particulate material which may be produced according to the previous cited process and which has a BET surface area of at least 10 m<2>/g. The material is particularly useful in the manufacture of Lithium Ion batteries.

Polycrystalline materials of macroscopic size exhibiting Single-Crystal-Like properties are formed from a plurality of Single-Crystal Particles, having Self-Aligning morphologies and optionally ling morphology, bonded together and aligned along at least one, and up to three, crystallographic directions.

A photocatalytic composite material having a photocatalytic titanium oxide film on the surface of a substrate is produced by a CVD method in which TiCl₄ vapor is reacted with water vapor. The TiCl₄ vapor and the water vapor are injected into a vapor deposition chamber (9) through nozzles (5) and (6), respectively, such that the resulting two injected vapor streams meet before reaching the substrate, thereby mixing the two vapors. Within 3 seconds after this mixing, the mixed vapors are brought into contact with a substrate (1) which is moving in one direction. Preferably the TiCl₄ vapor is injected in a reverse direction with respect to the direction of movement of the substrate through a multi-orifice nozzle (5), while the water vapor is injected through a slit nozzle (6) disposed at a smaller angle with respect to the substrate.

A process for preparing the hydrosol of nano-class anatase-type TiO2 features that reaction between Ti-contained organic substance, distilled water or deionized water, chelating agent and hydrodecomposing inhibitor at 30-120 deg.C for 3-12 hr while stirring and controlling pH=1-5.

This invention relates to a 4 group metal oxide and to a method for preparation thereof and the 4 group metal oxide prepared by adding a particle growth inhibiter to a hydrosol a hydrogel or a dried product of a hydrous 4 group metal oxide represented by MO(2-x)(OH)2x (wherein M denotes a 4 group metal and x is a number greater than 0.1 or x>0.1) followed by drying and calcining has a specific surface area of 80 m<2>/g or more, a pore volume of 0.2 ml/g or more and a pore sharpness degree of 50% or more and excellent heat stability and is useful for a catalyst or a catalyst carrier in which a catalyst metal is dispersed to a high degree. This invention further relates to a porous 4 group metal oxide and to a method for preparation thereof and the 4 group metal oxide prepared by application of a pH swing operation is characterized by a large specific surface area, excellent heat stability, high dispersion of a catalyst metal and a controlled and sharp pore distribution and is useful for a catalyst or a catalyst carrier of excellent reaction selectivity.

A dye-sensitized solar cell comprising a semiconductor electrode comprising electrospun ultra-fine titanium dioxide fibers and fabrication method thereof are disclosed. The dye-sensitized solar cell comprises a semiconductor electrode comprising an electrospun ultra-fine fibrous titanium dioxide layer, a counter electrode and electrolyte interposed therebetween. A non-liquid electrolyte such as polymer gel electrolyte or the like having low fluidity, as well as the liquid electrolyte, can be easily infiltrated thereinto. In addition, electrons can be effectively transferred since titanium dioxide crystals are one-dimensionally arranged.

This invention discloses a method for preparing neutral titanium dioxide nanosol. The method comprises: (1) preparing amorphous titanium dioxide; (2) dispersing and dissolving amorphous titanium dioxide; (3) performing hydrothermal treatment to obtain neutral titanium dioxide nanosol. The obtained neutral titanium dioxide nanosol (below 10 nm) is transparent and golden, and does not have any odor. Besides, the neutral titanium dioxide nanosol has such advantages as high stability, certain crystallinity, high specific surface area, high adhesiveness, reduced particle sizes after doped with transition metal, and high utility of visible light. The method has such advantages as wide raw materials and easy operation, and is suitable for large-scale production.

Disclosed herein are core-shell type nanoparticles comprising nanoparticle cores made of a metal or semiconductor, and shells made of crystalline metal oxide formed on the surfaces of the nanoparticle cores, as well as a preparation method thereof. According to the disclosed invention, the core-shell nanoparticles, consisting of metallic or semiconductor cores and crystalline metal oxide shells, can be prepared by epitaxially growing metal oxide on the surfaces of the metallic or semiconductor nanoparticle cores. By virtue of the crystalline metal oxide shells, the core nanoparticle made of metal or semiconductor can ensure excellent chemical and mechanical stability, and the core-shell nanoparticles can show new properties resulting from the interaction between the metal cores and the metal oxide crystal shells.

Micelle-templated superficially porous particles having a solid core and an outer porous shell with ordered pore structures and a narrow particle size distribution, such as about ±5% (one sigma), and a high specific surface area of about 5 to about 1000 m²/g.

The invention relates to a method for recycling titanium dioxide in a waste SCR (Selective Catalytic Reduction) denitration catalyst. The method comprises the following steps of: firstly removing dust from the waste denitration catalyst, pulverizing, then adding concentrated sulfuric acid so as to carry out acid hydrolysis on the waste denitration catalyst to obtain a concentrated titanyl sulfate solution, and adding water for dilution; adding a non-ionic emulsifier serving as a flocculating agent and a sulfonate surface active agent or a polycarboxylate surface active agent as a coagulant aid, and adding water-solubility methyl silicone oil; pumping into a plate-and-frame filter press for filter pressing, carrying out vacuum concentration on filtrate, then heating to 90 DEG C to 98 DEG C, and maintaining for 5.5 hours so as to hydrolyze the filtrate; cooling a hydrolysis product to 40 DEG C, and carrying out vacuum filtration so as to sediment out metatitanic acid; rinsing with sand-filtered water and deionized water, and adding potassium carbonate or phosphorous acid to obtain metatitanic acid filter cakes; and drying the filter cakes, calcining at 500-800 DEG C, and then pulverizing to obtain a titanium dioxide finished product. The method has the advantages of being capable of reducing disposal amount of the waste denitration catalyst, recycling the waste denitration catalyst and reducing the production cost of the waste denitration catalyst.

Nanomaterials of the JT phase of the titanium oxide TiO_2-x, where 0≦x≦1 having as a building block a crystalline structure with an orthorhombic symmetry and described by at least one of the space groups 59 Pmmn, 63 Amma, 71 Immm or 63 Bmmb. These nanomaterials are in the form of nanofibers, nanowires, nanorods, nanoscrolls and/or nanotubes. The nanomaterials are obtained from a hydrogen titanate and/or a mixed sodium and hydrogen titanate precursor compound that is isostructural to the JT crystalline structure. The titanates are the hydrogenated, the protonated, the hydrated and/or the alkalinized phases of the JT crystalline phase that are obtained from titanium compounds such as titanium oxide with an anatase crystalline structure, amorphous titanium oxide, and titanium oxide with a rutile crystalline structure, and/or directly from the rutile mineral and/or from ilmenite. The titanates are submitted to dynamic thermal treatment in an inert, oxidizing or reducing atmosphere to produce the JT phase of the TiO_2-x, where 0≦x≦1 with an orthorhombic structure.

Methods of treatment for medical indications having a microbial etiology are provided using polybiguanides, particularly water insoluble and complexed with a water insoluble antimicrobial metal material. The compositions are contacted with mucosal or dermal tissue susceptible to infection or infected in an amount sufficient to inhibit proliferation and with a spaced-apart regimen due to the persistence of the composition.

This invention relates to methods of making single phase nanocrystalline titanium dioxide. It is hereby provided a method for preparing single-phase anatase type titanium dioxide photocatalyst having a particle size of nano level at near room temperatures without the need for a sintering process at high temperatures.

The invention relates to a method for preparing an ordered porous anodic titanium dioxide nanotube array. The method can prepare an ultra-large area defect-free titanium dioxide nanotube array film, the surface layer is the porous shape like an anodic aluminum oxide template, and the lower layer is a nanotube ordered array, thereby overcoming the common problems of easy lodging and aggregation of tubes in the prior art of preparing the anodic titanium dioxide nanotube array and simultaneously solving the problems that the prepared nanotube array film has more surface defect corrosion pits and the sediment blocks tube mouths. The nanotube array can realize the controllable growth by controlling the preparation conditions and the process and obtain the ordered array films with different tube diameters, different wall thicknesses and different tube lengths. The diameter range of the nanotubes is 20-200nm, the wall thickness range is 5-30nm, and the length range of the titanium dioxide tubes is 100nm-1mm. The invention particularly relates to a technology which can effectively and completely strip the titanium dioxide array film, effectively strip a titanium substrate from the TiO2 nanotube array and obtain the different sizes of porous nanotube array self-support films.

The present invention is directed to producing nano-structured particles that have high specific surface-areas and high thermal stability. By aging nanoparticle precursors, and processing them under appropriate conditions, one is able to generate nano-structured particles that may be used in catalysts. By adding a stabilizing agent one is able to further improve the high thermal stability. These nano-structured particle products are particularly advantageous in applications as catalysts or catalyst supports that operate at high temperatures.

Provided is a method of manufacturing a metal oxide film to be formed through the following processes: a coating process of forming a coating film on a substrate by using a coating liquid for forming metal oxide film containing any of various organometallic compounds; a drying process of making the coating film into a dried coating film; and a heating process of forming an inorganic film from the dried coating film under an oxygen-containing atmosphere having a dew-point temperature equal to or lower than −10° C.

Disclosed are a method for fabricating nanopowders, nano ink containing the nanopowders and micro rods, and nanopowders containing nanoparticles, nano clusters or mixture thereof, milled from nano fiber composed of at least one kind of nanoparticles selected from a group consisting of metal, nonmetal, metal oxide, metal compound, nonmetal compound and composite metal oxide, nano ink containing the nanopowders and microrods, the method comprising spinning a spinning solution containing at least one kind of precursor capable of composing at least one kind selected from a group consisting of metal, nonmetal, metal oxide, metal compound, nonmetal compound and composite metal oxide, crystallizing or amorphizing the spun precursor to produce nano fiber containing at least one kind of nanoparticles selected from a group consisting of metal, nonmetal, metal oxide, metal compound, nonmetal compound and composite metal oxide, and milling the nano fiber to fabricate nanopowders containing nanoparticles, nano clusters or mixture thereof.

The present invention involves increasing the quantum efficiency in titania photocatalysts for photocatalytic (oxidation of acetaldehyde) and photosynthetic (photosplitting of water) reactions by integrating the titania photocatalyst with a polar mineral having surface electrical fields due to pyroelectric and piezoelectric effects, and by adjusting the nanostructure of the photocatalyst materials. The photocatalytic reactivity of titania powder is increased due to the effect of electric field present on the surface of polar mineral material on the photocatalytic effect of commercial titania with respect to photolysis of water. Additionally, the photocatalytic performance of pure phase rutile and anatase nanostructures with well defined morphologies was found to improved with respect to certain photocatalytic reactions in comparison with non-structured titania.