3744results about How to "Improve photocatalytic performance" patented technology

The invention discloses a preparation method of a visible light catalyst. Compared with the prior art, the invention adopts inexpensive, non-toxic and harmless urea as the raw material, with no need for highly toxic raw materials. By controlling the calcination temperature, C3N4 can be prepared, thus being in favor of environment protection. The invention also provides a preparation method of a visible light catalyst, comprising the steps of: preparing C3N4 according to the above process; mixing the obtained C3N4 with a modifier in a solvent for reaction, drying the reaction product, thus obtaining the visible light catalyst. The modifier can be an Fe source compound, a Cu source compound, a Zn source compound, a V source compound, a W source compound, a Pt source compound, an Au source compound or a Pd source compound. The method of the invention employs an immersion method for C3N4 metal ion modification, so that metal ions can adsorb the C3N4 surface, thus inhibiting photoinduced charge recombination. Therefore, the visible light catalyst prepared by the preparation method provided in the invention has a high photo catalytic performance.

The invention relates to a titanium dioxide/graphene nanocomposite material, a preparation method of the nanocomposite material and application of the nanocomposite material in the field of energy source and cleaning environment. The graphene accounts for 1-25wt% and the balance is titanium dioxide. Morphology of the titanium dioxide is a mesoporous structure or a structure with a dominant high energy surface, and titanium dioxide is scattered uniformly on the surface of graphene. According to the invention, by adopting a titanium source and graphene as initial materials, and water or organic solvents as reaction solvents, the nanocomposite material with titanium dioxide with the mesoporous structure or a titanium dioxide nano sheet with the dominant high energy surface compounded with graphene can be obtained through hydrothermal synthesis or a hydrolysis reaction. The invention can be carried out in an aqueous solution system and the crystallinity of the product is high. The composite material can be applied to a cathode material of a power ion battery, has a higher charge-discharge capacity, is excellent in high current charge and discharge, stable in circulating performance, has very good photocatalytic performance and can be used to light degradation of organic pollutants and water photolysis for preparing hydrogen.

A composite photocatalyst is provided. The composite photocatalyst includes a nanomotor and a plurality of cocatalysts, the nanomotor comprises a shell formed by porous material, at least one inner core formed by a photocatalyst, and a cavity between the shell and the at least one inner core, the plurality of cocatalysts are located in the cavity. The plurality of cocatalysts are selected from the group consisting of metal nanoparticles, metal oxide nanoparticles, metal sulfide nanoparticles, phosphate nanoparticles, up-conversion material nanoparticles, and any combination thereof. A method for making the composite photocatalyst and application thereof are further provided. The plurality of cocatalysts and the nanomotor forms a photocatalytic synergistic reaction system, improving photo-catalytic activity of the composite photocatalyst.

The invention provides a method for preparing an SiO2/TiO2 hollow microsphere by a sol-gel method. The method is mainly characterized in that cation polystyrene microsphere (PS) is used as a formwork; ethyl silicate and butyl titanate are respectively used as raw material and diluted ammonia is taken as regulator of pH value; a multi-layer organic-inorganic hybrid composite microsphere is obtained by the sol-gel reaction under the temperature of 70-80 DEG C. Formwork particle of the obtained deposition is removed by a calcining process to obtain the SiO2/ TiO2 hollow microsphere. By changing the consistency of reactant, content of surfactant and calcining temperature, the SiO2/ TiO2 hollow microsphere with different spherical shell thickness, density and grain size can be obtained. The hollow microsphere prepared by the method has high photo-catalytic activity, overcomes the shortage that existing preparation method of hollow microsphere can only prepare single shell layer microsphere; the multi-layer hollow microsphere can be prepared, the technique is simple, the cost is low and the preparation method of the invention is suitable for industrialized production.

The invention relates to a preparation method for an organic-inorganic composite separation membrane with hydrophilicity and the function of photocatalytic degradation of pollutants. The steps include: (1) blending a magnetic composite photocatalytic material composed of the magnetic particle @TiO2 with a graphene oxide loaded core-shell structure, polymer resin, a solvent and an additive to prepare a membrane casting solution; (2) placing the obtained membrane casting solution in a 100-20000 Gauss magnetic field to prepare a membrane, after 10-200sec, immersing the membrane into a coagulation bath for 30-120sec coagulation, taking the membrane out of the coagulation bath, carrying out washing, soaking and drying, thus obtaining the composite separation membrane with the function. By applying the action of a magnetic field in the evaporation and coagulation process of membrane formation, migration of the magnetic composite photocatalytic material in the membrane casting solution to the surface of a separation membrane can be realized, thus solving the problem that during inorganic nano-material blending modification of the separation membrane, nano-materials are mostly embedded in a membrane matrix, and the modification effect of the nano-materials cannot be brought into full play. The surface of the polymer separation membrane is endowed with good hydrophilicity and the property of photocatalytic degradation of pollutants.

Multi-functional materials which have a photocatalytic layer with a photocatalytic function disposed on the surface of a base through a binder layer 6 interposed therebetween. Photocatalytic particles of the photocatalytic layer are joined together by a surface energy or solid-state sintering. The photocatalytic layer may have a structure in which fine particles fill interstices defined between photocatalytic particles or a structure in which no fine particles fill interstices defined between photocatalytic particles. A metal such as Ag, Pt, or the like may be fixed or not fixed to surfaces of the photocatalytic particles.

A preparation method of a two-dimensional nitrogen-doped carbon-based titanium dioxide composite material includes: (1) etching Ti₃AlC2 with LiF/HCl to prepare two-dimensional transition metal carbide nanosheet; (2) preparing a nanosheet aggregate by electrostatic self-assembly of a two-dimensional transition metal carbide nanosheet and a positively charged nitrogen-containing cationic compound; (3) calcining the nanosheet aggregates to prepare a two-dimensional nitrogen-doped carbon-based titanium dioxide composite material. A method for degrading and removing organic pollutants in water includes (1) etching Ti₃AlC₂ with LiF/HCl to prepare two-dimensional transition metal carbide nanosheet; (2) preparing a nanosheet aggregate by electrostatic self-assembly of a two-dimensional transition metal carbide nanosheet and a positively charged nitrogen-containing cationic compound; (3) calcining the nanosheet aggregates to prepare a two-dimensional nitrogen-doped carbon-based titanium dioxide composite material; (4) placing the two-dimensional nitrogen-doped carbon-based titanium dioxide composite material into water containing organic pollutants to degrade and remove organic pollutants in water.

The invention relates to a silver-modified carbon nitride composite photocatalytic material and a preparation method thereof. The preparation method comprises: dissolving dicyanodiamide or melamine in deionized water or dimethyl sulfoxide and performing ultrasonic dispersing, so as to obtain a dicyanodiamide or melamine dispersion liquid; dissolving silver nitrate in deionized water and stirring uniformly, so as to obtain a silver nitrate solution; slowly dropwise adding the silver nitrate solution into the above dicyanodiamide or melamine dispersion liquid under the condition of magnetic stirring, and continuing stirring the solution, so as to obtain a mixed precursor solution; using anhydrous ethanol and deionized water repeatedly wash the obtained mixed precursor solution for multiple times, and performing vacuum drying; and putting the obtained product in a proper crucible and covering, putting in a high-temperature furnace, and sintering for a period under the condition of nitrogen protection, so as to obtain a powdery sample. The advantages comprise that the raw material source is wide, the preparation technology is simple and practicable, and the cost is relatively low; and the prepared composite photocatalytic material has relatively good photocatalytic degradation effect on organic dye rhodamine B under irradiation of visible light.

The inveniton provides a hydrophilic modification method for a polytetrafluoroethylene membrane. The method comprises the following steps: step 1, subjecting the polytetrafluoroethylene membrane to plasma treatment under a nitrogen atmosphere, and allowing the surface of the polytetrafluoroethylene membrane to generate relatively-stable free radicals and active sites; step 2, placing the polytetrafluoroethylene membrane into an acylic acid solution and carrying out static impregnation for a period of time, then taking the polytetrafluoroethylene membrane out of the solution and then placing the polytetrafluoroethylene membrane between two glase plates, and carrying out thermochemical polymerization in a vacuum drying oven so as to obtain the polytetrafluoroethylene membrane with the surface grafted with polyacrylic acid; and step 3, subjecting the polytetrafluoroethylene membrane to static impregnation in a titanium dioxide sol for a period of time, and allowing titanium dioxide to be assembled onto the surface of the polytetrafluoroethylene membrane through the coordination effect of metal titanium-ion Ti4+ and a carboxyl group on the polyacrylic acid so as to obtain a hydrophilic modified polytetrafluoroethylene membrane. The hydrophilic modified polytetrafluoroethylene membrane prepared by using the method in the invention retains excellent properties of a conventional polytetrafluoroethylene membrane and greatly improves filter performance, hydrophilic property, pollution resistant property and photocatalytic property of the polytetrafluoroethylene membrane.

The invention relates to a silver doped grapheme-zinc oxide nano composite photocatalytic material and a method for preparing the same and belongs to the technical field of nano composite materials and photocatalysis. Graphite oxide is subjected to ultrasonic dispersion to obtain a dispersion solution of graphene oxide; precursors of silver ions and zinc ions are added in the dispersion solution of the graphene oxide, and the mixture is placed into a reaction kettle to be subjected to hydro-thermal treatment to be prepared into the silver doped grapheme-zinc oxide nano composite photocatalytic material in situ after the pH is regulated to an alkaline condition. Photocatalytic degradation experiments show that the silver doped grapheme-zinc oxide nano composite photocatalytic material prepared through the method has good adsorption and visible light photocatalytic degradation effects on rhodamine B and is an ideal nano composite photocatalytic material.

The invention relates to an organic wastewater treatment film reactor utilizing solar energy photo-assisted electro-catalysis, which comprises a storage tank of water to be processed, a flow controllable constant flow pump, a photoelectric chemical reactor, a clear water storage tank and a solar battery component, wherein a photo anode and a cathode are correspondingly arranged in the reactor; the photo anode takes a porous metal membrane as a base body, and a TiO2 nano tube or a TiO2 mesoporous membrane is formed on the surface of a porous titanium membrane (net) by an electrochemical anisotropic etching technology; a porous channel film is used as the base body; a metal oxide coating electrode with high electrochemical catalytic activity and high electrical conductivity is prepared by a dipping film-forming method, simultaneously, by doping and modifying operations, the electrode material has photo catalytic activity and the reaction efficiency is improved. The reactor integrates electrochemistry, photocatalysis and film separation technologies; the three technologies are coupled to enhance a synergistic effect; the wastewater treatment efficiency can be improved; a solar component is adopted as a power supply; the clean solar energy is utilized to the maximal degree, and the organic wastewater treatment film reactor has social benefits of reducing environment load and economic benefits of reducing cost.

The invention discloses a preparation method of a metallic oxide/N-doped carbon nano tube composite material. The preparation method comprises the following steps of: (1) ultrasonically dispersing an N-doped carbon nano tube in a mixed solution of water and alcohol to obtain a solution A; (2) under the condition of stirring, dripping a solution B into the solution A, and stirring to obtain a mixed solution, wherein the solution B is water and/or alcoholic solution containing metal ions; and (3) carrying out solid-liquid separation on the mixed solution, and washing, drying and roasting to obtain the metallic oxide/N-doped carbon nano tube composite material. The invention also provides the composite material obtained through the method and an application thereof. According to the preparation method disclosed by the invention, as a method of solution phase synthesis under the condition of room temperature is adopted, hydrothermal reaction and solvothermal reaction with high temperature and high pressure are avoided, and the composite material with tighter combination of the metallic oxnide and the /N-doped carbon nano tube can be obtained. By adopting the preparation method, the preparation cost is low, the operation is simple, the preparation condition is mild, and the reaction period is also short.

The present invention relates to a low temperature treating process of self-cleaning TiO2 nanoglass. By using silica and anatase type nanosol as basic components and through pulling process, film is formed on the surface of glass plate. The film is dried at room temperature and cured or treated at temperature below 300 deg.c and cooled naturally. The prepared self-cleaned glass has excellent photocatalytic property, superhydrophilic property, high and homogeneous transparency. The said process is simple, low in cost and suitable for industrial production.

A photocatalytic material containing tungsten trioxide fine particles having an average particle diameter of 0.5 μm or smaller and a crystal structure of a monoclinic crystal system as a main component.

The invention relates to a process for preparing diatom earth loading nanometer Ti2O material for purifying water and air, which belongs to the field of material process and environmental treatment. Diatom earth raw ore is filled with water and is churned and scattered, is screened, is sunken by gravity, and is eccentrically sunken, sulfuric acid is adopted to dissolve clay-type foreign matters which are left in pore passages after ores which mutually grow with diatom earth like quartz, feldspar, mica, and clay and the like and organic matters which are mixed such as grass roots and barks and the like are removed, and diatom fine soil is attained. Further, diatom fine soil is filtered, dried, and baked, and diatom fine soil after baked is filled with water, and is churned, and is filled with acid to regulate the PH value, and is filled TiCl4 solution, and is filled with ammonia sulfate solution to proceed hydrolytic decomposition deposition reaction, and product yield after the reaction is filtered, washed, dried, and baked to attain the nanometer Ti2O material.

The invention relates to a recoverable TiO2-SiO2 composite aero-gel photo-catalyst as well as the preparation method thereof. The invention is characterized in that the sol-gel method is firstly utilized for respectively preparing TiO2 sol and SiO2 sol, then the two are mixed according to a certain proportion to obtain a mixed sol, and then TiO2-SiO2 composite alcogel is obtained through polycondensation reaction; the TiO2-SiO2 composite alcogel is used for preparing TiO2-SiO2 composite aero-gel after drying, and the composite aerogel is used for obtaining composite aero-gel aggregates after baking for 6 to 8 hours. The pore size of the obtained composite aero-gel aggregates is distributed between 2.5 nm to 10 nm, and the particle diameter is distributed between 10 nm to 15 nm, while the particle diameter of the aggregates is distributed between 0.1 mm and 0.3 mm. Compared with the prior art, the TiO2-SiO2 composite aero-gel photo-catalyst has the advantages that the prepared TiO2-SiO2 composite aero-gel has large specific surface area, high porosity, uniform pore distribution, etc., wherein, TiO2 is in the anatase crystal form. Compared with the TiO2 nanometer powder absorbent, the photo catalytic activity of the TiO2-SiO2 composite aero-gel is higher, the photo catalytic efficiency is better, and the regeneration and the reuse of the composite aero-gel are convenient as the particles of the aero-gel aggregates are larger, thereby the recoverable TiO2-SiO2 composite aero-gel photo-catalyst is widely applicable to the treatment of a great amount of wastewater.

The invention discloses a method for regulating river branch black and odorous water bodies by using a graphene modified nano titanium dioxide photocatalyst fiber net. The method comprises the following steps: (1) preparing a reduction-oxidation graphene modified nano titanium dioxide hetero-structure composite photocatalyst; (2) preparing a water-resistant and impact-resistant aluminum-based crosslinking agent to form a homogeneous mixture with the catalyst, adding the homogeneous mixture into fiber stuff for producing a high-density polyethylene fiber net, or also preparing a high-density polyethylene fiber net provided with a nano photocatalysis film coating; (3) performing natural drying in the air, and then performing drying at a constant temperature in a drying room; and (4) arranging the graphene modified nano titanium dioxide photocatalyst high-density polyethylene fiber net on a river branch to contact with the water surface and receive illumination at the same time so as to control the river branch black and odorous water bodies. The method disclosed by the invention does not need aeration oxygenation, is energy-saving and environment-friendly, and is lower in cost and simpler in process.

The invention discloses a nano-titanium dioxide composite material for wastewater treatment, which is composed of (a) nano-titanium dioxide, (b) adsorptive porous material and (c) nano-titanium dioxide modified material; the nano-titanium dioxide modified material includes Inert metals Ag, Au, Pt or/and transition metal ions Cr, Mn, Fe, Co, Ni, Cu or/and rare earth metal ions La ³⁺ , Y ³⁺ 、Eu ³⁺ Or/and Fe‑Sn, Fe‑La. The nano-titanium dioxide composite material of the present invention is composed of nano-titanium dioxide modified material, nano-titanium dioxide, and adsorptive porous material, which improves the photocatalytic activity of nano-titanium dioxide and the utilization rate of light, as well as the utilization rate of nano-titanium dioxide. The decomposition of matter has a significant effect.

The invention provides a grading three-dimensional porous graphene/titanium dioxide photocatalyst and preparation method thereof. The photocatalyst is composed by a three-dimensional grapheme framework and nano titanium dioxide particles; the grahene is provided with a macroporous structure; titanium dioxide is mesoporous titanium dioxide; the macropores and the mesopores are communicated; the nano titanium dioxide particles are scattered on a grapheme nano sheet; the surfaces of nano titanium dioxide microspheres are wrapped with graphene nano sheets; the macropores of the graphene are filled with the nano titanium dioxide microspheres. The photocatalyst with a three-dimensional structure can not only prevent the graphene sheet layers from stacking, but also scatter titanium dioxide particles excellently, and is high in specific surface area; besides, samples can be used for photocatalysis degradation of methylene blue, and the methylene blue can be fully degraded in 25 minutes. The preparation method provides a new thought for preparation of the photocatalyst, and has a potential application value in the fields of energy sources and environment.

The invention belongs to the technical field of functional concrete, and relates to a concrete material having a function of purifying gas-solid pollutants. The concrete material is characterized by being prepared from the components of cement, fine aggregate, coarse aggregate, water, water reducing agent, photocatalyst, an alkali solution and retarder, wherein the cement is 260-530 kg/m<3>, the silica fume content is 0-10 wt% of the cement content, the fly ash content is 0-25 wt% of the cement content, and the slag content is 0-40 wt% of the cement content; the coarse aggregate is 255-850 kg/m<3>, and the sand ratio is 30-45%; the water is 155-220 kg/m<3>; the mixing amount of the water reducing agent accounts for 0.5-1.2% of the total weight of the cement; the photocatalyst is 5-25 g/m<2>; the retarder content accounts for 0.01-1.0% of the weight of the cement to be removed on the surface layer of the concrete; the photocatalyst is put into the alkali solution to prepare a mixture; and the concentration of the photocatalyst is 1-5 g/L. The concrete material prepared by the method has a function of purifying gas-solid pollutants.

The invention relates to the field of synthesis of nano-materials and particularly relates to a method for synthesizing a series of Ag:ZnIn2S4 luminescent quantum dots by using a simple and rapid hydrothermal method in one step. Fluorescence is adjustable in the range of 460nm to 830nm, the fluorescent life is relatively long, and the luminescent quantum dots can be applied to water-decomposed hydrogen production under visible light. The method comprises the steps of firstly, mixing and dissolving silver nitrate, indium nitrate, zinc acetate dihydrate and L-cysteine in an aqueous solution, adjusting the pH value of the solution to 8.5 by using NaOH, adding thioacetamide into the solution, carrying out ultrasonic stirring, then, carrying out a hydrothermal reaction for 4 hours at the temperature of 110 DEG C, and carrying out centrifugal drying after the reaction ends, thereby obtaining Ag@ZnIn2S4 nanocrystals of different ratios. Proven by a photocatalytic hydrogen production experiment under the visible light, the prepared composite photocatalyst has good photocatalytic activity.

The multifunctional green nano paint consists of mainly: quaternary methacrylic acid-butyl acrylate-styrene-methyl methacrylate copolymer emulsion 20-65 wt%; nano titania 0.3-5 wt%; nano zinc oxide 0.2-3 wt%; silica 0.3-3 wt%; nano calcium carbonate 0.5-5 wt%; deionized water 3-12 wt%; superfine talcum powder 1-3 wt%; superfine calcium carbonate 3-15 wt%; titanium white3-25 wt%; and assistants including dispersant, wetter, rheologic agent, thickener, color paste, defoaming agent, etc. 2-12 wt%. The paint of the present invention features no toxicity, no pollution, wash resistance, scratching resistance, ultraviolet resistance, ageing resistance, waterproofing and mould proofing as well as self-cleaning function, so that the paint may be used wide in the decoration of inner and outer walls and the anticorrosive treatment of metal material surface.