362results about How to "Broaden the photoresponse range" patented technology

The invention relates to a BiVO4 nano photoelectrode and application thereof in the aspect of hydrogen production from water splitting, which can increase photocurrent and greatly improve the efficiency of quantum conversion. The BiVO4 nano photoelectrode comprises a BiVO4 nano-pore thin film, and BiVO4 is doped with metal cation, wherein the metal cation is one or a mixture with an arbitrary proportion of more than two of Sr<2+>, Ba<2+>, Cr<6+> and W<6+> by arbitrary proportion. As an improvement of the invention, the surface of the BiVO4 nano-pore thin film is also modified with a catalyst, wherein the catalyst is one or a mixture with an arbitrary proportion of more than two of the oxides of the hydroxides of Rh, W, Mo, Co, Fe, Mn and Ni. Compared with a pure BiVO4 electrode, the quantum conversion efficiency of the invention is greatly increased and reaches 70 percent within a wavelength range of 360-450nm, and a photoresponse range is broadened to 510nm.

The invention relates to a nano particle taking Fe3O4 as core, in particular to a TiO2/SiO2/Fe3O4 nano particle with nuclear structure and manufacturing method thereof. The invention solves the technical problems that nano TiO2 particle catalyst has low catalytic efficiency under natural light and is difficult to meet recovery control while remaining high catalyst activity in sewage treatment. The method includes steps of preparing SiO2/Fe3O4 solution, preparing titanium sol and mixing the prepared SiO2/Fe3O4 solution and the titanium sol. The invention adopts ferromagnetic particle as a carrier core and prepared TiO2/SiO2/Fe3O4 particle with nuclear shell structure as catalyst, and the catalyst particle has good dispersity and water-solubility and can be fully contacted with organic pollutant in sewage, thereby not only having high efficiency of suspended phase photocatalyst but also realizing magnetic control of catalyst by super paramagnetic nuclear energy, thus being effectively recovered.

The invention discloses a preparation method of black titanium dioxide. The method comprises steps of 1) first, preparing butyl titanate and absolute ethyl alcohol into a mixing system A; 2) preparing distilled water and glacial acetic acid into a mixing system B; 3) adding the system A into the system B with stirring, stirring at a normal temperature and placing overnight; 4) then heating at a constant temperature with stirring until generation of gel, adding glacial acetic acid again and completely washing by stirring; and drying, grinding and sieving the gel, insulating under protection ofinert gas and cooling to room temperature in furnace to obtain the black titanium dioxide powder. The preparation technology of the present invention is simple and easily realized; besides, the blacktitanium dioxide prepared under protection of inert gas of the invention not only has better sunlight absorption capability than present white titanium dioxide, but also can effectively expand a light response scope into a visible light scope.

The invention discloses synthesis of nitrogen-doped graphene quantum dot/similar-graphene phase carbon nitride composite material and research and application of photocatalytic decomposition of aquatic hydrogen performance. A catalyst is composed of a nitrogen-doped graphene quantum dot and similar-graphene phase carbon nitride. Under simulated sunlight, the catalyst can efficiently and stably achieve water photolysis to produce hydrogen. The synthesis and application have the advantages that the catalyst is completely composed of nonmetal elements and has the advantages of being environmentally friendly and low in cost; the light response range of the similar-graphene phase carbon nitride is enlarged due to the doping of the nitrogen-doped graphene quantum dot, and absorption under the visible light is increased; the photosensitization effect and the ultrastrong electron conduction capacity of the nitrogen-doped graphene quantum dot are utilized at the same time, photo-induced electron and hole composition is restrained, and meanwhile the light utilization rate is improved; the raw materials are low in cost and easy to obtain, the synthesis method is simple, the synthesis yield and purity are high, and experimental repeatability is good.

The invention relates to a yttrium oxide/ titanium dioxide nanometer composite material. The component quality percentage is 0.1-75 of Y2Ti2O7, 10-45 of anatase TiO2 and 10-70 of rutile TiO2. The preparation method for nanometer powder is that sol-gel method is used to combine with the simple roasting and so it is provided with relative simple technology, easy operation, low demand for equipment and low cost. Compared with pure TiO2, the yttrium oxide/titanium dioxide nanometer composite material prepared in invention has higher catalytic capability. Actually the anatase titanium oxide composite Y203 is the decoration to TiO2 grain so that the charge separation effect of system can be improved and the TiO2 spectral response range is enlarged. The size of grain of obtained product is equal and the spectral response range is enlarged. It can be applied widely in water pollution treatment, waste gas treatment and bacteria disinfection so on.

The invention belongs to the field of photocatalytic materials, and particularly relates to a near-infrared light compound photocatalyst and a preparation method thereof. The compound photocatalyst is formed by mechanically mixing an up-conversion luminescent material beta-NaYF4: Yb<3+>, Tm<3+> and a photocatalytic material Degussa P25, wherein the up-conversion material is used for absorbing near-infrared light which is converted, so that ultraviolet light is emitted, and the utilization of near-infrared light is realized by exciting the photocatalytic activity of TiO2, and the utilization efficiency of sunlight in light-catalyzed reaction is increased. The near-infrared light compound photocatalyst can be applied to the field of light catalysis environmental management.

The invention provides a graphene modified composite mesoporous carbon microsphere air purifying preparation. A certain amount of beta-cyclodextrin is added to thin-layered nano-SiO2 particles covering the surfaces of obtained micro-SiO2 particles, a certain quantity of obtained RGO/TiO2 nanoparticles is added simultaneously, -OH, -COOH, C-O-C and C=O oxygen-containing functional groups rich on the surface of graphene are adsorbed by and bonded with the RGO/TiO2 nanoparticles on the basis of the molecular recognition characteristic of beta-cyclodextrin, then a certain amount of CTAB (cetyltrimethylammonium bromide) surfactant is added, CTAB serving as a micelle stabilizer can stop the RGO/TiO2 nanoparticles from further hydrolysis and growth, and finally, the novel air purifying preparation adopting RGO/TiO2 supported by carbon microspheres with a mesoporous shell structure is obtained. With adoption of the scheme, the purity is high, RGO/TiO2 supported by the carbon microspheres with the mesoporous shell structure in powder is better in bonding performance, uniform in distribution and controllable in dimension at mesopores, and the air purifying preparation can be used for purifying polluted air and removing dust in a haze environment as well as photo-catalytically degrading and separating nitric oxide, sulfide or other organic pollutants in the polluted air.

The invention discloses a synthetic method for high-activity N-F co-doped bismuth vanadate visible light photocatalytic material prepared through the citric acid complexation sol-gel method and a preparation process. The method employs Bi(NO3)3.5H2O(97%) and NH4VO3(98.5%) as source materials, citric acid(99.5%) as a chelating agent, NH4F as N and F sources, and utilizes ammonium hydroxide to regulate the pH value, and dark blue sol is prepared, dried, calcined to obtain the N-F co-doped bismuth vanadate photocatalytic material. When the material is compared to bismuth vanadate without being doped, because of the synergistic effects of N and F, oxygen vacancies and V4+ with catalytic activity are increased N-F co-doped bismuth vanadate crystals, the band-gap energy is narrower and the photocatalytic activity is raised obviously in visible light. The method is advantaged by simple process, mild conditions and good repeatability. The photocatalytic material can be widely used in photocatalytic degradation of organic pollutants, and has wide application prospects in environmental governance.

The invention discloses a supported photocatalyst with high activity under visible light and a preparation method thereof. The preparation method is characterized by comprising the steps of: preparing a polyvinyl alcohol-titanium dioxide composite film by using a sol-gel method, and subjecting the polyvinyl alcohol-titanium dioxide composite film to a certain thermal treatment. A polymer is combined with an inorganic matter by using chemical bonds to form a mutually-crosslinked net structure which has better film-forming performance and can be loaded on inorganic carriers such as glass, ceramic, silicon gel, metal and the like. The method has the advantages of wide sources of raw materials, lower cost and simple and controllable preparation process; and the prepared photocatalytic material under the visible light and can be used for effectively degrading organic pollutants.

The invention provides a preparation method of a composite photocatalyst CdS/n-TiO2 for catalyzing and decomposing H2S to prepare hydrogen and relates to a preparation method of a composite photocatalyst. The preparation method solves the problem of low hydrogen generation rate when H2S is optically catalyzed and decomposed by CdS/TiO2. The preparation method comprises the following steps: ultrasonically dispersing, drying, grinding and roasting nanometer TiO2 in a dispersing agent to obtain n-TiO2; adding the n-TiO2 in a cadmium salt solution and a vulcanizing agent solution to obtain yellow gelatinous precipitates; and obtaining the composite photocatalyst CdS/n-TiO2 by hydrothermally processing, cooling, washing and filtering the precipitates and drying filter residues. Compared with the CdS/TiO2 photocatalyst, the composite photocatalyst obtained by the preparation method increases the hydrogen generation rate by 28 percent to 52 percent under visible light.

The invention belongs to the technical field of catalyst preparation, and relates to a visible light photocatalyst BiOCl with a cotton-shaped structure and a preparation method thereof; the visible light photocatalyst BiOCl is prepared by adopting a room temperature chemical method; the prepared BiOCl photocatalyst has the unique cotton-shaped structure formed by stacking ultrathin nanosheets; the special structure endows the BiOCl photocatalyst with relatively large specific surface area and excellent adsorption performance, so that the photoresponse range of the BiOCl is widened to a visible light region, and the BiOCl can successfully rapidly degrade a stable pollutant methyl orange under visible light irradiation; and the product has the advantages of large specific surface area, high photocatalytic efficiency, simple preparation process, convenient operation, low cost, high yield and high purity.

The invention provides a platinum atom-loaded titanium dioxide photocatalytic material and a preparation method thereof. The preparation method of the photocatalytic material comprises the following steps: 1), dispersing nanometer titanium dioxide in deionized water to form a titanium dioxide dispersion; 2), adding a platinum precursor into the titanium dioxide dispersion, and uniformly mixing bystirring to obtain a mixed solution A, wherein the mass of platinum is 0.3-1.5% of that of the titanium dioxide; 3), performing a photoreduction reaction on the mixed solution A under light irradiation to reduce the platinum precursor into elemental platinum, and loading the platinum precursor onto the nanometer titanium dioxide to obtain a mixed solution B; 4), centrifuging the mixed solution B to obtain a precipitate, and washing and drying the precipitate to obtain the platinum atom-loaded black titanium dioxide photocatalytic material. According to the preparation method, the platinum is uniformly and highly dispersively loaded onto the titanium dioxide through control of the using amount of the platinum precursor, platinum atoms are deposited by an in-situ photoreduction technology, and the existing form of the platinum atoms on the surface of the black titanium dioxide is controlled through control to the addition amount of chloroplatinic acid, so that the photocatalytic effect is improved.

The invention relates to a method for modifying a photocatalyst TiO2 by using WO3 and a rare earth metal element La. The method comprises the following steps: dispersing a precursor tetrabutyl titanate into a solvent absolute ethyl alcohol, performing a hydrolysis reaction to obtain nanometer TiO2 particles, and introducing a semiconductor material WO3 and a rare earth metal element La in a reaction process, wherein the mol ratio of the Ti:WO3:La is 100:(0-10):(1-6), and the WO3-La/TiO2 nanometer compound photocatalyst is uniform in size, better in dispersity, free from toxicity and secondary pollution, low in price of raw materials and stable in source, simple in synthesis process without secondary pollution, low in price and stable in source of raw materials, simple in synthesis process without pollution, excellent in performance, and wide in application range, can be repeatedly used, can be conveniently prepared into a powdery coating or other types of green environmental-friendly material, is applied to pollution removal and purification of various environments, and has a wide practical application value in the aspect of preparation of a photoelectric material or photocatalysis material.

The invention relates to a preparation method of an adsorption-photocatalysis compound type formaldehyde removing coating, relating to a preparation method of a coating and aiming at solving the problems of low formaldehyde degradation efficiency and incapability of enriching formaldehyde in an existing photocatalysis coating. The preparation method disclosed by the invention comprises the following steps: (1), preparing ACF (Active Carbon Fiber) modified by concentrated nitric acid; (2), mixing butyl titanate, ethanol and acetic acid; (3), mixing ethanol, acetic acid and water, adding urea and iron nitrate nonahydrate crystals, and adjusting pH; (4), preparing TiO2 sol containing iron and nitrogen; (5), preparing ACF loaded with TiO2; (6), preparing TiO2/ACF compound powder; and (7), mixing the TiO2/ACF compound powder with the coating. By means of the enrichment action of ACF, the problem of low TiO2 efficiency is solved to a great extent; by means of the catalytic action of TiO2, the saturated regeneration problem of an adsorbent is effectively solved; the characteristics of the ACF and the TiO2 are complementary; the formaldehyde degradation efficiency is greatly improved. The preparation method disclosed by the invention can be used for preparing the adsorption-photocatalysis compound type formaldehyde removing coating.

The invention discloses a rGO/Fe<3+>/g-C3N4 ternary composite photocatalyst. The rGO/Fe<3+>/g-C3N4 ternary composite photocatalyst is obtained by mixing an aqueous iron ion solution and tripolycyanamide, drying, grinding and calcinating to obtain an Fe-C3N4 photocatalyst, protonating the Fe-C3N4 photocatalyst, then mixing with graphene oxide, drying and calcinating. The invention further disclosesa preparation method of the rGO/Fe<3+>/g-C3N4 ternary composite photocatalyst. The preparation method comprises the following steps: (1), preparing the Fe-C3N4 photocatalyst: weighing a certain amount of iron salt, dissolving in deionized water, adding the tripolycyanamide, uniformly mixing, drying, calcinating, and cooling to obtain the Fe-C3N4 photocatalyst; (2), protonating the Fe-C3N4 photocatalyst; (3), dissolving graphene oxide powder in deionized water, ultrasonically dispersing, adding the protonated Fe-C3N4 powder, uniformly mixing, stirring, drying, grinding, and calcinating to obtain the rGO/Fe<3+>/g-C3N4 ternary composite photocatalyst.

The invention belongs to the technical field of chemical coatings, and in particular, relates to a modified nano titanium dioxide self-cleaning coating and a preparation method thereof. The preparation method comprises the following steps: adding 1.5-3 parts of boron and nitrogen doped and coated nano titanium dioxide into an ethanol aqueous solution, stirring and dispersing, adding 0.5-2.5 parts of an organic silane coupling agent, carrying out stirring and heat preservation reaction, then carrying out suction filtration, drying and grinding to obtain silanized boron and nitrogen doped and coated nano titanium dioxide; dispersing 1.5-3 parts of the silanized boron and nitrogen doped and coated nano titanium dioxide into a mixed solution of 15-25 parts of an acrylate monomer and 0.5-2 parts of a co-emulsifier, stirring, carrying out ultrasonic dispersion, then adding 2-6 parts of an emulsifier and 50-90 parts of deionized water, stirring, carrying out ultrasonic dispersion, adding 0.3-0.6 part of an initiator, and carrying out heat preservation for 3-5 h, to obtain the modified nano titanium dioxide self-cleaning coating. The self-cleaning coating has the advantages of good dispersion of titanium dioxide and strong self-cleaning ability.

The invention belongs to the field of new chemical materials and in particular relates to a carbon quantum dot/attapulgite nanocomposite as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing citric acid, hydrogen peroxide and attapulgite, carrying out hydrothermal reaction, and then centrifuging, washing and drying, so that the carbon quantum dot/attapulgite nanocomposite is obtained, and then the nanocomposite is used for photocatalytic desulphurization.

The invention discloses a plasma-type tungsten oxide-modified graphite phase carbon nitride nanosheet composite photocatalyst and a preparation method and application thereof. The composite photocatalyst comprises a plasma-type tungsten oxide and a graphite phase carbon nitride nanosheet. The plasma-type tungsten oxide attaches to the surface of the graphite phase carbon nitride nanosheet. The plasma-type tungsten oxide is W18O49. The preparation method comprises mixing the graphite phase carbon nitride nanosheet and a tungsten hexacarbonyl solution to obtain a precursor mixed solution and preparing a composite photocatalyst through a hydrothermal reaction. The composite photocatalyst has the advantages of high photocatalytic activity, wide photoresponse range, stable photocatalytic performance and good recyclability. The preparation method has the advantages of simple processes, operation easiness and low cost. The composite photocatalyst can be used for treating antibiotic waste water, can be used through a simple method, realizes a low cost, has a high removal rate, effectively degrades antibiotics in waste water and has a good application prospect.

The invention discloses an amorphous plasma heterojunction nano TiO2 sol having high-efficiency visible light response as well as a preparation method and an application thereof. The amorphous plasma heterojunction nano TiO2 sol is formed by taking a heterojunction structural body formed by precious metals and nano TiO2, or other semiconductor-precious metals and nano TiO2 by chemical connection as nano particles, schottky junction generated by cooperation among precious metals and nano TiO2 or other semiconductor-precious metals and nano TiO2 is used for performing resonance effects with local surface plasma to obtain the excellent visible-light photocatalysis effect, and the problem of low visible-light utilization rate of common TiO2 photocatalysts can be solved.

The invention discloses a preparation method of a zinc oxide/zinc titanite nucleocapsid nanowire composite photocatalyst and application thereof, belonging to the technical field of environment pollution disposal. The preparation method of the catalyst comprises the following steps: 1) preparing a zinc oxide nanowire template by using a water heat process, wherein the diameter of the nanowire is about 200 nm, and the length of the nanowire is about a plurality of microns; 2) adopting a sol-gel wet chemical process to uniformly wrap a layer of titanium dioxide outside the zinc oxide nanowire template; and 3) sintering at a high temperature so as to generate solid phase reaction and then obtaining the zinc oxide/zinc titanite nucleocapsid nanowire. The method has the advantages of simple operation, room temperature implementing, stable performance, green synthesis process and the like. The composition of the zinc titanite not only expands the photoresponse scope of the zinc oxide nanowire and improves the separation efficiency of electron holes but also improves the photocatalyst degradation efficiency of organic pollutants, thereby having high practical value and great application prospect.

The invention discloses a preparation method of an efficient photocatalyst nitrogen doped meso-porous niobium pentoxide. The preparation method comprises a step of the preparation of meso-porous niobium pentoxide and a step of the preparation of nitrogen doped meso-porous niobium pentoxide. The preparation method can effectively develop the light response range of a niobium pentoxide photocatalyst, substantially enhance the catalytic activity of a photocatalyst under the condition of the sunlight, and further enlarge the application field of the niobium pentoxide photocatalyst. The efficient photocatalyst nitrogen doped meso-porous niobium pentoxide has the characteristics of rapid and effective decomposition of water, high recovery rate and no secondary pollution, and is an environmentally-friendly photocatalyst.