3986results about How to "Improve photocatalytic activity" patented technology

The present invention provides a photocatalyst composite in which brittleness and ease of coming-off of a photocatalyst layer are reduced.

The photocatalyst composite includes a base material, at least the surface of which is formed of a plastic-deformable solid material; an inorganic particle layer containing inorganic particles disposed on the surface of the base material; and a photocatalyst layer containing a photocatalyst disposed on the surface of the inorganic particle layer; wherein at least one portion of voids in the inorganic particle layer is filled with the solid material, and the surface of the inorganic particle layer is coated with the solid material except for at least one portion.

The invention discloses a high-efficiency graphene/silver phosphate composite visible light photocatalyst and a preparation method thereof, belonging to the technical field of composite materials and environmental management photocatalysis. The preparation method comprises the following steps: dissolving graphene oxide in water, and carrying out ultrasonic treatment to obtain a graphene oxide dispersed liquid; dissolving silver nitrate in deionized water, gradually and dropwisely adding into the graphene oxide dispersed liquid while stirring to obtain a mixed solution, uniformly stirring, and aging; dropwisely adding a prepared disodium hydrogen phosphate or sodium dihydrogen phosphate solution into the graphene oxide-silver nitrate mixed solution, continuing stirring, transferring into a hydrothermal reaction kettle, carrying out hydrothermal reaction, and cooling to room temperature; and washing the reaction product, and carrying out vacuum drying to obtain the visible light photocatalyst. The invention has the advantages of wide material sources and simple preparation process; and the obtained composite material has the advantages of controllable structure and regular pattern, and has high-efficiency degradation effect on organic dyes rhodamine B and methylene blue with certain concentration under the visible light irradiation.

The invention relates to a kieselguhr-based porous ceramics, a preparation method thereof and a method for loading Ag doped with nano TiO2 on the same, belonging to the technical field of a kieselguhr inorganic material. The kieselguhr-based porous ceramics is made from kieselguhr, a sintering auxiliary agent, a dispersing agent, a binder and water in the weight ratio of 60-92:8-40:0.01-2:0:001-1:100-450. The kieselguhr-based porous ceramics has functions of absorption and filtration, and can absorb granules in fluid when the fluid passes through the lieselguhr-based porous ceramics. Ag doped with nano TiO2 is loaded on the kieselguhr-based porous ceramics to generate kieselguhr-based porous ceramics loading the Ag doped with TiO2. The laden anatase-type nano TiO2 has large specific surface area. The effects of filtration, photochemical catalysis and sterilization of the kieselguhr-based porous ceramics loading the Ag doped with nano TiO2 are greatly increased.

The invention discloses a method for preparing a TiO2/g-C3N4 composite visible light catalyst. The method comprises the following steps: firstly, uniformly dispersing a titanium source and a nitrogen source in ethanol, and subsequently dropping water into ethanol so as to obtain a mixed material; evaporating to dry the mixed material in a stirring state so as to obtain a precursor; transferring the prepared precursor to a muffle furnace, and calcining for 0.5-12 hours at 300-800 DEG C in the muffle furnace, thereby obtaining the TiO2/g-C3N4 composite visible light catalyst. The TiO2/g-C3N4 composite visible light catalyst can be prepared while TiO2 and g-C3N4 are prepared, and the synthesis of the two compounds TiO2 and g-C3N4 and the preparation of the composite visible light catalyst are achieved at one step; the process is simple, and industrialization production is easy to achieve. The composite visible light catalyst disclosed by the invention is rich in photocatalytic activity center, relatively high in both light absorption rate and photocatalytic activity, and relatively high in photocatalytic degradation rate of organisms.

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.

The invention relates to a carbon quantum dot, precious metal and zinc indium sulfide composite photocatalyst and a preparation method thereof. The composite photocatalyst contains a hexagonal-phase zinc indium sulfide (ZnIn2S4) matrix, and reduced carbon quantum dots and precious metal particles which are carried on the surface of the ZnIn2S4 matrix, wherein the ZnIn2S4 matrix is of a peony-flower-shaped structure, the particle size of the matrix is 0.1-10 micrometers and the BET specific surface area of the matrix is 10-200 m<2>/g; the particle size of the carbon quantum dots and the precious metal particles is 1-10 nm; precious metal refers to one or a mixture of some of gold, platinum, silver or palladium. The composite photocatalyst has high catalytic activity (with a hydrogen production rate up to 1mmol.h<-1>g<-1>) under irradiation of visible light (more than or equal to 400nm), and has long service life (over 50 hours).

The invention relates to a method for manufacturing a magnetic loading type nanometer catalyst TiO2/Fe2O4. The method comprises the following steps of: using ferrous sulfate, ferric sulfate and ammonia as raw materials to prepare black nanometer Fe3O4 particles with good dispersivity through a coprecipitation process; coating one layer of TiO2 with optical catalyst on the Fe3O4 surface by a sol-gel process, and forming a TiO2/Fe3O4 composite material with a core-shell structure; carrying out heat treatment and recycling to obtain a magnetic loading type nanometer catalyst TiO2/Fe2O4. The catalyst not only has good optical catalytic activity, but also can utilize the outer magnetic field to realize convenient and quick recovering and reutilization, thereby decreasing the cost of waste water treatment and realizing the practical application of nanometer TiO2 in wastewater treatment.

A general-use white color reflecting material, and a process for production thereof are provided. The white color reflecting material, without troublesome surface treatment such as formation of a reflective layer by plating, is capable of reflecting a near-ultraviolet ray of a wavelength region of 380 nm or longer or a near-infrared ray sufficiently without light leakage; does not become yellow even when exposed to near-ultraviolet rays; has excellent lightfastness, heat resistance, and weatherability; has high mechanical strength and chemical stability; is capable of maintaining a high degree of whiteness; and is easily moldable at a low cost. Further a white color reflecting material used as an ink composition for producing the white color reflecting material in a film shape is also provided. The white color reflecting material comprises; a silicone resin or silicone rubber formed from titanium oxide-containing silicone composition, in which anatase-type or rutile-type titanium oxide particles are dispersed.

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 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.

Disclosed is a photocatalyst with excellent, stable photocatalytic activity. The photocatalyst contains a crystal having a nasicon structure. Here, the nasicon structure is represented by AmE2 (XO4)3 (in the formula, a primary element A is one or more selected from the group composed of Li, Na, K, Cu, Ag, Mg, Ca, Sr and Ba; a secondary element E is one or more selected from the group composed of Zn, Al, Fe, Ti, Sn, Zr, Ge, Hf, V, Nb, and Ta; a tertiary element X is 1 or more selected from the group composed of Si, P, S, Mo, and W, and the coefficient is 0 or more, or 3 or less.)

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.

The invention discloses an oxygen-doped carbon nitride/zinc oxide photo-catalyst as well as a preparation method and application of the oxygen-doped carbon nitride/zinc oxide photo-catalyst. The preparation method comprises the following steps: taking dicyandiamide or melamine as a precursor, calcining to prepare a carbon nitride nanosheet; adding a zinc oxide precursor into absolute ethyl alcohol, then adding dethylenetriamine, carrying out ultrasonic dispersion and subsequently enabling dispersion liquid to be subjected to hydrothermal reaction, so as to obtain zinc oxide nano material; enabling the zinc oxide nano material and the carbon nitride nanosheet to be subjected to ultrasonic dispersion in deionized water, subsequently adding hydrogen peroxide, then carrying out hydrothermal reaction again, and thus obtaining the oxygen-doped carbon nitride/zinc oxide photo-catalyst after the reaction is ended. The oxygen-doped carbon nitride/zinc oxide photo-catalyst adopts low-cost and easily available raw materials; the preparation condition can be easily achieved; the raw materials do not need to be calcined under the condition of high temperature, so that the cost for preparing the oxygen-doped carbon nitride/zinc oxide photo-catalyst is reduced, and the popularization and application of the preparation method are facilitated; meanwhile, the photo-catalyst is low in photo-production electron-cavity compounding efficiency and high in photo-catalytic activity.

The invention discloses a technology for preparing organic fuel through directly converting carbon dioxide by using sunlight and a photothermal catalyst. Sunlight is utilized to supply light and heat for the synthesis and catalytic process of the photothermal catalyst, and the photothermal catalyst can simultaneously absorb and utilize ultraviolet light, visible light and infrared light parts in sunlight, so that a phtothermal catalytic reaction is induced to prepare the organic fuel through reducing carbon dioxide by using hydrogen. The photothermal catalyst comprises the following components: an active component which is a 2-30 nano-scale non-stoichiometric oxide belonging to a VIII-family element in a transition family and a carrier material which is an oxide or carbon material with the specific surface area of 30-1000cm<2>/g, alkaline resistance, high heat conductivity or photocatalytic activity. A steeping and in-situ sintering method or photodepositing and in-situ sintering method is used as a synthesis method so that the energy consumption is low, and the photothermal catalyst has high activity and long service life by using a solar-assisted in-situ sintering technology. The technology for preparing organic fuel through directly converting carbon dioxide by using sunlight and the photothermal catalyst is low in energy consumption in the catalytic process, high in organic fuel production efficiency and stable in catalyst activity.

The present invention relates to a synthetic method of graphitic carbon nitride material. The method involves a homogenous mixing of carbon nitride precursor and ammonium salt, and calcining the mixture to obtain a porous graphitic carbon nitride material. Wherein, the ammonium salt is any one or a combination of at least two which could release gaseous NH₃ during thermolysis. The present invention uses thermolabile ammonium salt as a pore former; the thermolysis of ammonium salt could release soft gas bubbles during the calcination; the later burst of bubbles leads to the formation of nanoporous structure. The proposed method is template-free and environmentally-friendly, and the resultant material exhibits high photocatalytic activity in the field of gas and water decontamination.

The invention relates to a graphene/TiO2-based near-infrared/ultraviolet radiation resistant polymer composite film and a preparation method thereof, relating to a near-infrared/ultraviolet radiation resistant composite film and a preparation method thereof. The invention aims to solve the problems of the existing heat reflecting material such as poor heat insulation effect, low transparency, serious light pollution and high production cost and the like. The composite film is prepared by adding the mixed liquid of graphene oxide dispersion and nano-TiO2 dispersion in the curing system of epoxy acrylate at a volume ratio of 1-10:50. The preparation method comprises the following steps: 1) preparing graphene oxide; 2) preparing TiO2 nanoparticles; 3) preparing nanometer graphene/TiO2 composite; and 4) preparing the graphene/TiO2-based near-infrared/ultraviolet radiation resistant polymer composite film. The composite film is mainly used for the glass coating of a building or means of transport for running an air-conditioning system.

The invention provides a composite fiber material applied to visible light photocatalytic purification of sewage and air pollutants and a preparation method thereof. The composite fiber material is synthesized by loading a visible light response type bismuth-based photocatalytic material on a textile fiber material through a green chemical synthetic route. A powdered photocatalyst is solidly loaded by the unique net-like felt structure of the textile fiber material, so that the catalyst is prevented from losing and agglomerating during sewage treatment and air purification, and the separability and reusability are improved.

The invention discloses a preparation method of a tin sulfide material. A solvothermal method is adopted, dehydrate-stannous chloride is used as a tin source, the morphology and particle size of the synthetic material are controlled by controlling a sulfur source, the reaction temperature, reaction time, the solvent variety and the surfactant variety, and the SnS photocatalytic material with controllable morphology and high quality is prepared. The method is simple in preparation and easy to carry out, the yield is high, consumed time is short, cost is low, reaction conditions are mild, good development prospects are achieved, industrial production is easy to achieve, and the prepared material has high photocatalytic activity and has good industrial application prospects when serving as the photocatalytic material.

The invention provides an activated carbon-loaded cuprous oxide photocatalyst which can be used as a photocatalyst for degrading the organic pollutant such as phenols and purifying the air, wherein a preparation method of the activated carbon-loaded cuprous oxide photocatalyst comprises the following steps of: dipping the treated activated carbon in copper sulfate solution, and reducing by C6O12O6 or Na2SO3. The invention has the beneficial effects that the preparation of the activated carbon-loaded cuprous oxide photocatalyst takes copper sulfate as raw material, takes the activated carbon as a carrier, and loads the cuprous oxide on the activated carbon, so that the photocatalyst is simple in preparation method, low in cost, good in stability, and high in photocatalytic activity. The photocatalyst can be directly used for catalytically oxidizing the waste water such as the phenols and purifying the indoor air under an ultraviolet-visible light condition, so that the method is easy to operate, mild in reaction condition, and high in pollutant removing ratio.

The present invention provides a broad band light absorbing photocatalyst which has a high absorptivity not only for visible light but also, in particular, for ultraviolet light, exhibits photocatalytic activity in response to a broad band light over a long period, has a high adsorptivity for objects to be decomposed, and can exhibit oxidative decomposition effect, antibacterial effect, antifouling effect, etc. The broad band light absorbing photocatalyst of the present invention includes an apatite having photocatalytic activity, a visible light absorbing metal atom and an ultraviolet light absorbing metal atom and the ultraviolet light absorbing metal atom is at least one of tungsten (W) and vanadium (V).

The invention relates to a preparation method of echinoid titanium dioxide microspheres in single/double layer cavity structure, belonging to the field of nano composite materials. The method comprises the following steps: (1) preparing monodisperse silicon dioxide microspheres with uniform particle size; (2) by using silicon dioxide as a template, coating a titanium dioxide layer on the surface of the silicon dioxide microspheres by using a sol-gel method to obtain core-shell type silicon dioxide/titanium dioxide composite microspheres; (3) regulating the concentration of sodium hydroxide solution, the hydrothermal reaction time and other conditions, and preparing echinoid titanium-base microspheres in the single/double layer cavity structure in a controllable way; and (4) treating the echinoid titanium-base microspheres in the single/double layer cavity structure with hydrochloric acid with a certain concentration, and calcining at high temperature to obtain anatase-type echinoid titanium dioxide microspheres in the single/double layer cavity structure. The material prepared by the method has the high-activity pure-phase titanium dioxide crystal structure, and has the advantages of large specific area, complete appearance and high yield; the technical process is controllable and easy to operate; and the invention also has the advantages of low preparation cost, no pollution and low energy consumption.

The invention discloses a preparation method and application of a ZnIn2S4-graphene composited photochemical catalyst. The preparation method comprises the following steps of: placing graphite oxide into a reducibility alcohol agent for ultrasonic dispersion; adding zinc sulfate and indium chloride into the reducibility alcohol agent, stirring and dissolving; adding thioacetamide into two systems after the two systems are mixed; transferring the mixed systems into a hydrothermal kettle for a reaction; and after the reaction is finished, carrying out vacuum filtration on the obtained product, washing, vacuumizing and grinding to obtain a nano ZnIn2S4-graphene composited photochemical catalyst. In the invention, grapheme is taken as a supporting material, and a solvothermal synthesis method is adopted to further prepare the nano ZnIn2S4-graphene composited photochemical catalyst. The catalyst prepared by using the method in the invention has the advantages of wide visible light responding range and high photocatalysis activity, can be used for transformation and use of solar energy and comprehensive ecological improvement, such as air purification, sewage disposal, hydrogen production through photodegradation, preparation of alcohol or hydrocarbon chemical fuels and the like by the photocatalysis and reduction of CO2.