32results about How to "Visible light catalytic activity is good" patented technology

The invention discloses a BiVO4 / Bi2WO6 composite semiconductor material as well as a hydrothermal preparation method and an application thereof. The nominal composition of the BiVO4 / Bi2WO6 composite semiconductor material is (1-x) BiVO4 / xBi2WO6, wherein x is 5-95mol%. The composite semiconductor material prepared by the method has the advantages of good dispersity, controlled crystal structure and morphology, large special surface area and very good adsorption effect on organic dyestuff methylene blue, high visible-light response activity, good chemical stability and the like. The preparation method has the advantages of being simple in preparation technology, easy in obtaining of raw materials, low in energy consumption and environment-friendly and beneficial to mass production.

Provided are a visible-light catalyst Bi3O4Br and a preparation method thereof. The method comprises adding deionized water, bismuth salt and quaternary ammonium salt into a reaction kettle to obtain the bismuth salt with concentration of 0.02-0.04 molar / liter and the quaternary ammonium salt with concentration of 0.02-0.05 molar / liter, wherein the molar ratio of the bismuth salt to the quaternary ammonium salt is larger than or equal to one; adding caustic soda solution with concentration of 1 molar / liter into the mixture with stirring to regulate potential of hydrogen (pH) to be 11.0-12.5; stirring and performing hydro-thermal treatment at the treatment temperature of 160-180 DEG C; after keeping the constant temperate for 12-18 hours, centrifugally separating solid products; respectively washing the obtained solid products through the deionized water and absolute ethyl alcohol for at least three times; and drying the products at the temperature of 50 DEG C for at least 6 hours to obtain light-yellow Bi3O4Br solid powder. The Bi3O4Br has good visible-light activity and can have strong degradation to various pollutants under the irradiation of the visible light. In addition, the method is simple in synthesis, the whole synthesis process is easy to control, raw materials are easily obtained, and the cost is low.

The invention belongs to the technical field of TiO2 (titanium dioxide) photocatalysis. A preparation method for nitrogen-doped titanium dioxide powder of a reticulated porous structure is characterized by comprising the following steps: (1) extracting a nitrogen source, namely, selecting freshwater mussels at the ages of 2 to 6 years, and sucking covering liquid into a centrifugal pipe by using a pipette; (2) preparing mixed precipitate liquid, namely, weighing 0.5 to 5ml of tetrabutyl titanate in a beaker, measuring the covering liquid according to the volume ratio of the covering liquid to the tetrabutyl titanate equals being (5-10) to1, and dripping the covering liquid into tetrabutyl titanate to obtain the mixed precipitate liquid; (3) carrying out room-temperature mineralization; (4) carrying out hydrothermal synthesis of nitrogen-doped TiO2 powder; and (5) extracting the nitrogen-doped TiO2 powder. The nitrogen-doped TiO2 powder is successfully prepared at a low temperature by taking the covering liquid of living organisms as a biological template and the nitrogen source simultaneously, and adjusting the microstructure and the crystal form of the TiO2. According to the preparation method, the temperature is low, the cost is low, and the operation is easy; the prepared nitrogen-doped TiO2 powder has a bionic microstructure, namely nanoparticles assembled reticulated porous structure, and is large in specific area and high in crystallinity.

The invention discloses N-doped nano-TiO2 and a shock wave preparation method thereof, belonging to the technical field of material processing and combination. As for the N-doped nano-TiO2, the particle size is 5-20nm, the specific surface area is 98-355m<2> / g, and the N doping concentration is 2.7-4%. The preparation method comprises the following steps of: mixing metatitanic acid with dicyandiamide to get a powder preform, and utilizing instantaneous high temperature and high pressure generated by high-speed impact of a driven flyer plate to perform decomposition reaction on the metatitanic acid, wherein H2TiO3 is transformed to TiO2 and H2O; simultaneously decomposing a doped nitrogen source C2N4H4 under the action of shock waves; and enabling released N atoms to be synchronously doped into a TiO2 crystal lattice during the TiO2 forming process to get the N-doped nano-TiO2. The N-doped nano-TiO2 has the advantages of small particle size, large specific surface area, high N doping concentration and better visible light catalytic activity; and the preparation method has the advantages of low cost, simple technological process and completion within a short period of time.

The invention discloses PVC (polyvinyl chloride) wallpaper with a function of photocatalytically degrading formaldehyde in visible light and a method for preparing the PVC wallpaper. The method includes that urea is used as a nitrogen source, tetra-n-butyl titanate is used as a titanium source, and nitrogen-doped titanium dioxide (N-TiO2) photocatalysts are prepared by the aid of sol-gel processes; PVC wallpaper is used as a carrier, the photocatalysts N-TiO2 are carried on the surface of the PVC wallpaper to prepare the photocatalytic wallpaper. The PVC wallpaper and the method have the advantages that TiO2 sol is prepared by the aid of vacuum freeze drying processes, and accordingly the N-TiO2 photocatalysts which are high in photocatalytic activity as compared with like products prepared by the aid of the traditional hot-air drying preparation processes can be obtained, are high in crystallinity and have large specific surface area; formaldehyde gas can be degraded in the visible light by the photocatalytic PVC wallpaper prepared by the aid of the method, and the photocatalytic PVC wallpaper is high in photocatalytic activity.

The invention discloses a preparation method of high-dispersity g-C3N4 / TiO2 photocatalyst inorganic hydrosol and belongs to the field of functional materials. The method comprises the following steps of: adding a g-C3N4 / TiO2 photocatalyst into a water solution containing an inorganic dispersant according to a certain ratio under a stirring condition; adding a small amount of peptizing agent and adjusting the pH (Potential of Hydrogen) value of a suspension solution; and carrying out shear emulsifying and stirring treatment to obtain the stable high-dispersity g-C3N4 / TiO2 photocatalyst neutral inorganic hydrosol. A preparation process has a simple flow and is simple and convenient to operate; an organic dispersant and a solvent are not used and the preparation cost is low; the prepared photocatalyst hydrosol has high dispersity and stability and is suitable for preparing photocatalyst slurry and a coating agent; the application of the photocatalyst to the field of a coating material is facilitated.

The invention relates to a formaldehyde degradation experiment chamber, an experimental method and an application for degrading formaldehyde by using a photocatalyst and belongs to the technical field of environmental protection. The formaldehyde degradation experiment chamber comprises an experiment chamber, an air pump, a needle valve and a buffer container; a small-size fan, an exhaust port, a fluorescent tube and a carrier are arranged in the experiment chamber; the air pump is connected with the needle valve, the buffer container, the control valve and the experiment chamber in turn through a pipeline. The experiment chamber has a simple structure and is convenient for an application experiment of degrading formaldehyde by using the photocatalyst. In an airtight space, the initial value of formaldehyde is not above 1.5mg / m<3>, the concentration of the photocatalyst is controlled within 0.1-0.5mg / m<3>, the temperature and humidity in the airtight space are identical to each other, a fluorescent tube is used as a light source for irradiating, the degradation rate of formaldehyde within 2h under the existence of Cu-TiO2 photocatalyst is 57.3%, the degradation rate of formaldehyde within 2h under the existence of SO4-modified Co-TiO2 photocatalyst is 58.7% and the degradation rate of formaldehyde within 2h under the existence of CdxMn1-xS photocatalyst is 57.8%; the degradation rate of formaldehyde within 10h is above 95%; the preparation method for the photocatalyst is simple in process, high in doping efficiency, low in cost and suitable for indoor air treatment.

The invention relates to a compound Pt / TiO(2-x)Nx catalyst with the performance of preparing hydrogen through water decomposition by visible light as well as a preparation and application of the compound Pt / TiO(2-x)Nx catalyst. The catalyst is an aggregate formed by platinum particles and mesoporous nitrogen-doped titanium dioxide. The preparation method comprises the following steps: preparing titanium silicon compound oxide gel; preparing a mesoporous TiO(2-x)Nx compound solution; preparing platinum nanoparticle suspension; preparing the compound Pt / TiO(2-x)Nx catalyst. The catalyst is applied to preparation of the hydrogen by water photocatalytic decomposition taking the visible light as a light source. The preparation method disclosed by the invention has the advantages of being simplein process and equipment, easy to obtain, short in preparation period and easy in mass production; the obtained catalyst has the advantages of high specific surface area, wider visible light absorption range and high efficiency of preparation of the hydrogen through water decomposition by the visible light.

The invention discloses PVC (polyvinyl chloride) wallpaper with a function of photocatalytically degrading formaldehyde in visible light and a method for preparing the PVC wallpaper. The method includes that urea is used as a nitrogen source, tetra-n-butyl titanate is used as a titanium source, and nitrogen-doped titanium dioxide (N-TiO2) photocatalysts are prepared by the aid of sol-gel processes; PVC wallpaper is used as a carrier, the photocatalysts N-TiO2 are carried on the surface of the PVC wallpaper to prepare the photocatalytic wallpaper. The PVC wallpaper and the method have the advantages that TiO2 sol is prepared by the aid of vacuum freeze drying processes, and accordingly the N-TiO2 photocatalysts which are high in photocatalytic activity as compared with like products prepared by the aid of the traditional hot-air drying preparation processes can be obtained, are high in crystallinity and have large specific surface area; formaldehyde gas can be degraded in the visible light by the photocatalytic PVC wallpaper prepared by the aid of the method, and the photocatalytic PVC wallpaper is high in photocatalytic activity.

The invention relates to a preparation method and application method of a titanium dioxide nanosheet supported MIL-100 (Fe) composite photocatalysis material, belongs to the field of titanium dioxide photocatalysis, and especially relates to the field of titanium dioxide nanosheet supported porous metal organic skeleton (MOFs) composite materials. The preparation method comprises the following steps: 1, uniformly stirring tetrabutyl titanate and hydrofluoric acid at normal temperature, putting the obtained mixture in a hydrothermal reaction kettle, carrying out a reaction, separating the obtained material, washing the separated material, and drying the washed material to obtain titanium dioxide nanosheets; and 2, uniformly dispersing the titanium dioxide nanosheets in an anhydrous ethanol solution of iron trichloride, carrying out magnetic stirring at normal temperature for 15 min, carrying out suction filtration separation to obtain a product, dispersing the product in an anhydrous ethanol solution of trimesic acid, carrying out a 50-80 DEG C water bath reaction for 20-50 min, carrying out suction filtration separation to obtain a product, and repeating above processes in step 2 2-50 times to obtain the titanium dioxide nanosheet supported MIL-100 (Fe) composite photocatalysis material. The catalyst prepared through the method is especially suitable for catalytic degradation of high-concentration organic dyes (such as methylene blue) under visible light irritation) to reach a very high degradation rate.

The invention belongs to the technical field of TiO2 (titanium dioxide) photocatalysis. A preparation method for nitrogen-doped titanium dioxide powder of a reticulated porous structure is characterized by comprising the following steps: (1) extracting a nitrogen source, namely, selecting freshwater mussels at the ages of 2 to 6 years, and sucking covering liquid into a centrifugal pipe by using a pipette; (2) preparing mixed precipitate liquid, namely, weighing 0.5 to 5ml of tetrabutyl titanate in a beaker, measuring the covering liquid according to the volume ratio of the covering liquid to the tetrabutyl titanate equals being (5-10) to1, and dripping the covering liquid into tetrabutyl titanate to obtain the mixed precipitate liquid; (3) carrying out room-temperature mineralization; (4) carrying out hydrothermal synthesis of nitrogen-doped TiO2 powder; and (5) extracting the nitrogen-doped TiO2 powder. The nitrogen-doped TiO2 powder is successfully prepared at a low temperature by taking the covering liquid of living organisms as a biological template and the nitrogen source simultaneously, and adjusting the microstructure and the crystal form of the TiO2. According to the preparation method, the temperature is low, the cost is low, and the operation is easy; the prepared nitrogen-doped TiO2 powder has a bionic microstructure, namely nanoparticles assembled reticulated porous structure, and is large in specific area and high in crystallinity.

The invention relates to a preparation method for an alkali tantalate based composite visible-light photocatalyst in hydrogen production by water splitting, in particular to a method that ammonia is used as the nitrogen source to perform nitrogen doping on the alkali tantalate at high temperature. The method has the following steps: (1) dissolving the tantalum-containing precursor in the surfactant acidic solution to produce a uniform tantalum salt solution; (2) adjusting the PH value to 6-9 and adding the hydroxide of an alkali metal to produce a suspension; (3) water-heating the produced suspension in a reaction kettle to produce the alkali tantalate crystal and (4) treating the crystal with the ammonia to produce the alkali tantalate, and then obtaining the nitrogen doped alkali tantalate. The photocatalyst treats the alkali tantalate by high-temperature ammonolysis, which realizes nitrogen doping to the alkali tantalate. The experiment shows that the alkali tantalate is nitrogen doped in the preparation process which has good visible light catalysis and solves the problem of nitrogen doping to the alkali tantalate.

The invention discloses a g-C3N4 / Al2O3 / ZnO ternary heterojunction material with visible light catalytic activity and a preparation method thereof. The g-C3N4 / Al2O3 / ZnO ternary heterojunction material comprises, by weight 50-70% of g-C3N4, 45-20% of Al2O3 and 5-20% of ZnO. The preparation method of the g-C3N4 / Al2O3 / ZnO ternary heterojunction material comprises: dissolving suitable aluminum nitrate in distilled water, adding prepared g-C3N4 powder, stirring well, dropwise adding NaOH solution until pH is 8-9, stirring, dissolving in zinc nitrate, dropwise adding NaOH solution to maintain pH to 8-9, continuing to stir, filtering by suction, drying, and grinding to obtain a sample precursor, and calcining at 400 DEG C to obtain the g-C3N4 / Al2O3 / ZnO ternary heterojunction material. The preparation method is simple, the raw materials are low in rice, complex equipment is not required, the process is free of pollution, and the material is suitable for industrial batch production.

The invention relates a controllable synthesis method of nonmetallic ion-doped nano titanium dioxide by a phase separation-hydrolysis solvothermal method, in particular to a synthesis method of nonmetallic ion-doped nano titanium dioxide, which solves the problems of low doping efficiency, complicated process, high cost and poor universality of the existing nonmetallic ion doping method of the nano titanium dioxide. The synthesis method comprises the following steps: 1, mixing tetrabutyl titanate with methylbenzene and then stirring to obtain an organic phase; 2, adding nonmetallic ion aqueous solution to a high-pressure reaction kettle, placing the organic phase into a U-shaped groove, placing the groove into the nonmetallic ion aqueous solution, covering, carrying out solvothermal treatment, cooling and filtering; and 3, drying by oil bath and then roasting to obtain the nonmetallic ion-doped nano titanium dioxide. The synthesis method of the invention has simple process, high doping efficiency, low cost and wide applicability; and the obtained nano titanium dioxide has high crystallization degree and good visible light catalytic activity, thus the nano titanium dioxide can be applied to visible light catalytic degradation of organic pollutants.

The invention discloses a BiOCl / Al2O3 heterojunction material with photocatalytic activity and a preparation method thereof. The BiOCl / Al2O3 heterojunction material is composed of BiOCl and Al2O3 in a mol ratio of (0.4-2.0): 1. The preparation method for the BiOCl / Al2O3 heterojunction material comprises the following steps: (1) mixing bismuth nitrate, aluminum nitrate and diethylamine hydrochloride according to a mol ratio of (0.2-1.0): 1: (1.0-3.5) and heating the obtained mixture to a melting state so as to obtain ionic liquid; (2) continuing heating the ionic liquid obtained in the step (1) until the ionic liquid combusts; and (3) collecting solid produced after complete combustion in the step (2) and carrying out cooling and grinding so as to obtain the BiOCl / Al2O3 heterojunction material. The preparation method provided by the invention is simple in process, free of complex equipment, short in preparation time, high in yield, low in cost and suitable for industrial large-scale production.

The invention discloses a preparation method and application of boron hexaoxide. The present invention uses boron powder as a raw material, oxidizes crystalline boron, and utilizes its oxidation exothermic reaction to synthesize boron hexaoxide at low temperature, namely B 6 O. The preparation method of the present invention has low cost, low energy consumption and simple synthesis process, and the obtained boron hexaoxide has strong visible light absorption, and is first applied to photocatalytic decomposition of water to produce hydrogen and photocatalytic reduction of carbon dioxide, all of which show high stability and good performance. Visible light catalytic activity, and itself is a non-metallic photocatalyst, so it can have high scientific significance and application value in the field of new energy development.

The invention relates to a bismuth oxyiodide / porous titanium dioxide composite photocatalyst and its preparation method and application. It belongs to the field of photocatalysis. The technical scheme adopted is: disperse bismuth nitrate in ethylene glycol, add potassium iodide, keep stirring, then add porous titanium dioxide microspheres, and add ultrapure water, keep stirring for 1‑3h at room temperature, wash and dry the obtained product , to obtain bismuth oxyiodide / porous titanium dioxide composite photocatalyst. The invention synthesizes a porous titanium dioxide microsphere through a simple hydrothermal method, and the microsphere not only has a large specific surface area and uniform size, but is more conducive to light scattering. The bismuth oxyiodide / porous titanium dioxide composite photocatalyst synthesized with this kind of microsphere has a wide spectral response range, high photocatalytic activity under visible light, wide applicability and good stability, simple process, Easy to operate and low cost.

The invention provides a visible light photocatalyst Bi12O17Cl2 and a preparation method of the photocatalyst. The preparation method comprises the following steps of: dissolving bismuth nitrate pentahydrate and potassium chloride in water to prepare a mixed solution, wherein the molar ratio of bismuth nitrate pentahydrate to potassium chloride is 1:1; and adjusting the pH value of the mixed solution to 12.5-13, then carrying out hydrothermal treatment at 160-180 DEG C on the solution to obtain a solid product, and washing and drying the solid product to obtain the Bi12O17Cl2 product, which is nano sheets with length of a few hundreds of nanometers and width of a few hundreds of nanometers. Under the irradiation of visible light, the photocatalyst can realize that more than 99.5% and approximate 100% of target pollutant pentachlorophenol is degraded within 45 minutes. The method is simple in synthetic route, easy in whole process control, easy in raw material obtaining, low in cost, and high in yield (up to 90%), and is suitable for industrial large-scale production.

The invention relates to a benzimidazolone H3G / TiO2 compound photo-catalyst with a visible light response function and a preparation method thereof. A visible light absorbing area of the catalyst is 400-600nm. The preparation method comprises the following steps of: adding organic pigment benzimidazolone H3G, TiO2, an accelerator span 80, and N,N-dimethylformamide into an airtight high-pressure kettle; heating and increasing temperature; keeping temperature constant at 180-210 DEG C; after ending loading, cooling to room temperature; filtering, thereby obtaining a light yellow solid; respectively washing the solid with alcohol and water; and placing the obtained light yellow solid into a vacuum drying oven and drying at 100-150 DEG C, and then obtaining a benzimidazolone H3G / TiO2 compound photo-catalytic material. The method for preparing the benzimidazolone H3G / TiO2 photo-catalyst is called as a water thermal loading method in the invention for short. The catalyst provided by the invention has excellent visible light catalytic activity; the degradation speed of pollutant substance is higher than that of TiO2; the chemical and physical stabilities of the prepared catalyst are higher; after the catalyst is used, the catalyst is filtered, washed with distilled water and vacuum-dried for 0.5-1 hour at 100-150 DEG C, and then the catalyst is reusable; and after the catalyst is used for four times, the catalytic activity is not obviously reduced.

The invention provides a preparation method of low-temperature non-aqueous sol-gel of a high-activity carbon-chlorine codoped titanium dioxide visible light catalyst, and titanium dioxide is in anatase or rutile structure. The method comprises the following steps of: adding titanium salts into an organic solvent of alcohols and carbon-chlorine compounds; carrying out heat treatment on the whole mixture with low-temperature non-aqueous sol-gel, and then, carrying out suction filtration to obtain solid products; washing and drying the solid products; and changing the volume ratio of the alcohols to the carbon-chlorine compounds in the reaction system to obtain corresponding carbon-chlorine codoped titanium dioxide of different crystal forms. The anatase and rutile carbon-chlorine codoped titanium dioxide obtained in the reaction has good catalytic activity under visible light and can nearly completely degrade pollutants in about 2 hours under the irradiation of visible light. The methodhas the advantages of simple synthetic route, easy control of the whole technical process, low reaction temperature, easy acquisition of raw materials and low cost, enables the yield to reach 93%, and is suitable for industrial mass production.

The invention relates to a method for preparing a regular-triangular-pyramid-shaped bismuth germinate visible-light catalyst. The method is characterized by comprising the following steps: (1) under a stirring condition, according to the mole number 12:1:350 of bismuth nitrate pentahydrate: germanium oxide: sodium hydroxide, dissolving the bismuth nitrate pentahydrate and the germanium oxide into a 5mol / L sodium hydroxide solution to obtain a mixed solution A; according to the mole number 1:0.0039 of cetyl trimethyl ammonium bromide: sodium hydroxide, adding the cetyl trimethyl ammonium bromide into the obtained mixed solution A to obtain a mixed solution B; (2) carrying out heat treatment for 12 hours at 180 DEG C in a constant temperature oven; (3) after washing for 5 times, drying for 5 hours under the condition of constant temperature of 70 DEG C to obtain the regular-triangular-pyramid-shaped bismuth germinate visible-light catalyst. The method has the advantages that the preparation process is simple and easy to operate, the used raw materials are free from pollution and low in cost, the morphology and the crystal structure of the target product particles are controllable and the like. The prepared light catalyst has better visible-light catalytic activity for organic pollutants.

The invention discloses a dried persimmon-shaped visible-light-driven photocatalyst BiOBr and a preparation method thereof. The inventor adopts a low-temperature solvothermal method, controls the morphology of a halogen-bismuth-oxide visible-light-driven photocatalyst by controlling the dosage of a bismuth source and a bromine source and adding a structure guiding agent, and successfully prepares the novel efficient visible-light-driven photocatalyst BiOBr with novel and special morphology, the dried persimmon shape, for the first time. The preparation method disclosed by the invention is simple in overall production technology, easy to operate, low in synthesis temperature, high in reaction yield (89%), friendly to environment and low in cost, and accords with the requirements of practical production, and the raw materials are readily available. The visible-light-driven photocatalyst disclosed by the invention has good visible-light catalytic activity, can completely degrade a plurality of organic pollutants (such as methylthionine chloride and methyl orange) within a short period of time under irradiation of visible light, is small in light corrosivity, good in reusability and large in market potential, can be applied to industrial production, and especially has good application value in photocatalytic decomposition of organic pollutants by solar energy.