451results about How to "Reduced band gap" patented technology

This invention relates to TiO2 photocatalysis materials preparation, particularly relates to a classification carbon-doped titanium dioxide catalyst material and preparation method. This invention is a kind of the carbon-doped titanium dioxide with mesoporous - macroporous grade pore structure, carbon 3-25%, anatase phase, the big channel pore size of 300-1000nm, mesoporous aperture 2.0-24nm, the specific surface area can be as high as 691m2/g. The described material is prepared by titanate and carbon mixture hydrolysis product of the roasting 300-600deg.C, and preparation of equipment used simple, the described materials in organic dye molecules have good catalytic properties on the photodegradation.

The invention discloses a method for preparing an Ag/TiO2 nano composite material. Firstly liquid phase laser erosion is utilized to produce a TiOX colloid, and a silver nitrate solution is added to carry out hydro-thermal treatment, thus the Ag/TiO2 nano composite material is obtained. The TiOX colloid in the invention has small particles and high reaction activity; the method is characterized in that no organic reagent such as a reducing agent and a stabilizing agent is added; red shift is produced on light absorption of silver modified titanium dioxide, the forbidden bandwidth is reduced, and the utilization factor to sunlight can be effectively improved; and the method provides a new approach and thinking for realizing modification on a semiconductor material by virtue of ultramicro precious metal nano particles, meanwhile, the application range of the liquid phase laser erosion is widened.

The invention discloses preparation and use methods of a nitrogen -vanadium co-doped modified titanium dioxide catalyst, belonging to the technical field of preparation and use of catalysts. The preparation method comprises the following steps of: adding a nitrogen source and a vanadium source in a process of preparing titanium dioxide by using a sol-gel method; hydrolyzing the mixture to obtain gelatin and standing, aging and drying to form particles; then grinding and carbonizing and heating to 600 to 800 DEG C for roasting to obtain a mixed crystal type titanium dioxide catalyst with different doping amounts. The compounding of electron-hole pair is influenced by doping metal ions to improve utilization ratios of visible light.With simple operation and easy control, the prepared nitrogen -vanadium co-doped modified titanium dioxide catalyst can achieve greatly improved visible light activity and can be applied to sulphuric acid production in the chemical engineering industry, SO2 tail gas treatment in the smelting industry, sulfur dioxide control of coal-fired and fuel boilers, acid rain prevention and control, smoke gas adjustment of coal-fired power plants, improvement on the dust removal efficiency of an electric precipitator, and other fields.

The invention discloses a preparation method of a nanosheet self-assembled C-doped (BiO)2CO3 microsphere visible light catalyst, which comprises the following steps: (1) dissolving a bismuth-containing precursor, a soluble carbonate and a doping carbon source in a water solution, stirring for 30 minutes, transferring the obtained mixed solution into a high-pressure hydrothermal kettle, and carrying out hydrothermal reaction at 120-250 DEG C for 3-100 hours; and (2) after the hydrothermal reaction finishes, cooling, filtering out the precipitate, respectively washing the precipitate with deionized water and ethanol, and drying to obtain the nanosheet self-assembled C-doped (BiO)2CO3 microspheres. According to the C-doped (BiO)2CO3 prepared by the method disclosed by the invention, the doping C element reduces the energy gap of (BiO)2CO3, and the (BiO)2CO3 has visible light catalytic activity. The experimental result proves that the NO removal rate of the bismuthyl carbonate photocatalyst disclosed by the invention is 30-45%, which indicates that the bismuthyl carbonate photocatalyst has high visible light catalytic activity.

The invention belongs to the preparation fields of a photoelectric material and a thin film solar cell, and discloses a high-orientation antimony selenide thin film and a preparation method therefor, particularly an antimony selenide thin film with high orientation. The high-orientation antimony selenide thin film is a one-dimensional chain-like material; the high orientation refers to the thin film formed by the antimony selenide chin which is grown in a direction of <002>. The preparation method specifically comprises two steps of adopting a thermal evaporation method or other methods to prepare the antimony selenide thin film, and then performing a method for carrying out selenylation (sulfuration) processing. By adoption of the preparation method provided by the invention, the high-orientation antimony selenide thin film can be obtained; a more efficient antimony selenide thin film solar cell is expected to be obtained; and in addition, the preparation method is simple and feasible, and low in cost.

The invention discloses a magnetically supported titanium dioxide photocatalyst and a preparation method thereof, belonging to the technical field of material preparation. A solvothermal process is used for obtaining a dimension-adjustable ferroferric oxide spherical particles, and the pH value, reaction temperature, reaction time and other experimental parameters are regulated to control the hydrolysis of tetrabutyl titanate, so that the tetrabutyl titanate is uniformly supported on the surface of the ferroferric oxide magnetic nucleus, thereby preparing the hexagonal crystal form magnetically supported titanium dioxide photocatalyst. The magnetically supported titanium dioxide photocatalyst has the advantages of controllable preparation technique, high safety and reliability and high yield, can be used for quickly catalyzing the degradation of pollutants, and can be easy in industrialization production.

The present invention relates to a composite photocatalyst which can utilize sunlight and has good magnetic separating property and its preparation method. Said preparation method includes the following several steps: firstly, utilizing hydrothermal method to synthesize NiFeO4 nano granules, then utilizing homogeneous precipitation method to directly cover NiFeO4 magnetic nuclear surface by using TiO2 so as to form TiO2 external shell. Said composite photocatalyst can be used for making water supply treatment and waste water treatment.

The invention discloses a preparation method of oxygen-sulfur dual-doped graphite phase carbon nitride. The method comprises the following steps: performing one-step thermal polymerization on melamineand L-cysteine at a temperature of 400-700 DEG C according to a mass ratio (1.5-2.5):100 of the L-cysteine to melamine, thereby obtaining the oxygen-sulfur dual-doped graphite phase carbon nitride. According to dual doping in the invention, the element O and the element S respectively enter the graphite phase carbon nitride in a chemical bond form. The energy gap of the doped graphite phase carbon nitride is reduced, the impedance is reduced, the graphite phase carbon nitride has high photocatalytic activity, and the photocatalytic nitrogen fixation efficiency of 2.0% of GCNOS reaches 0.509 mMg<-1>h<-1> within 240 minutes, and reaches 2.1 times that of the photocatalytic nitrogen fixation efficiency of pure graphite phase carbon nitride.

The invention discloses a preparation method of a graphene oxide wrapped titania microsphere photocatalyst. By utilizing organic groups enriched on the surfaces of a titania microsphere and graphene, the prepared monodisperse titania microsphere interacts with a graphene oxide solution according to the esterification condensation reaction bonding principle under a definite condition, so that the graphene wrapped titania microsphere photocatalyst is prepared. According to the method, the graphene oxide and the titania are stably combined together. The method has the advantages of short experimental period, convenience for operation, rapid synthesizing speed, high efficiency and low in energy consumption. Therefore, the method can be applied to the industrial production.

The invention relates to a method for growth of a germanium nitrogen codoped silicon carbide single crystal material. A PVT method is adopted according to the method; in the germanium-doped silicon carbide single crystal growth process, nitrogen at a certain proportion is led into a growth atmosphere, argon is led in to serve as a carrier gas with the pressure controlled to be 700-850 mbar, argon flow is 15-30 sccm, and the nitrogen flow is 0.5-2 sccm; and the germanium nitrogen codoped silicon carbide single crystal is obtained. On the one hand, high-concentration germanium element doping is implemented, and on the other hand, by adjusting specific doping concentration of germanium and nitrogen, the goal of increasing silicon carbide crystal lattice fitness degree, reducing crystal stress and improving crystal quality is achieved. Application of the silicon carbide crystal material to visible light and infrared light wave bands is expanded.

The invention discloses a one-step synthesis method of nitrogen-and-sulfur co-doped titanium dioxide/graphene quantum dot heterostructure. The preparation method disclosed by the invention can synthesize a co-doped modified binary system through one step, and enable nitrogen-and-sulfur co-doped titanium dioxide and nitrogen-and-sulfur co-doped graphene quantum dots to be closely compounded together through a stronger chemical bond. The one-step synthesis method is mainly applied to the field of photocatalytic degradation; methylene blue is degraded under visible light; the photocatalysis performance of the composite material is detected through a degrading curve. Compared with the photocatalysis performance of single titanium dioxide, the photocatalysis performance of the composite material is substantially improved due to the excellent visible catalysis activity, and the composite material is environmentally friendly, cannot introduce heavy metal ions, cannot lead to secondary pollution to treated water resources, and is high in circulating stability.

The invention discloses a silver-doped zirconium dioxide photocatalyst which is mainly prepared from the following steps: 1) taking industrial-grade zirconium dioxide, putting in a muffle furnace, and carrying out high-temperature calcination to obtain an intermediate sample 1; 2) putting the intermediate sample 1 in a strongly alkaline solution, dropwisely adding a silver-ion-containing water solution while stirring, and continuing stirring to obtain an intermediate sample 2; 3) putting the intermediate sample 2 into a high-pressure autoclave, and carrying out hydrothermal reaction to obtain an intermediate sample 3; and 4) putting the intermediate sample 3 into a centrifuge tube, carrying out centrifuge washing until the pH value of the supernate is 7, and drying at normal temperature to obtain the silver-doped zirconium dioxide photocatalyst. The invention also discloses application of the silver-doped zirconium dioxide photocatalyst in photocatalytic water decomposition. The silver-doped zirconium dioxide photocatalyst fills up the blank in the silver-doped zirconium dioxide photocatalyst in the prior art, and has the advantages of uniform size, high photocatalytic water decomposition efficiency, simple preparation method and low production cost.

TiO_2-xN_x (0.01≦x≦0.2) nanotubes and a method for preparing the same are disclosed. More particularly, TiO_2-xN_x (0.01≦x≦0.2) nanotubes doped with nitrogen atoms by treating TiO₂ nanotubes through nitrogen plasma to partially substitute oxygen portion of TiO₂ nanotube with nitrogen, and a method for preparing the same are disclosed. The TiO_2-xN_x (0.01≦x≦0.2) nanotube of the present invention is prepared by doping nitrogen on a TiO₂ nanotube to control an electronic structure and reduce a band gap of the TiO₂ nanotube, so that the prepared TiO_2-xN_x (0.01≦x≦0.2) nanotube exhibits improved conductivity and extended light absorption range from a UV ray area up to a visible light area, thus having more enhanced applicable performance in optical and/or electrochemical aspects.

The invention relates to an Li and Mn codoped manganese phosphate/carbon composite material which is characterized in that a general formula of the Li and Mn codoped manganese phosphate/carbon composite material is Li[1-x]AxMn[1-y]ByPO4/C, wherein x is more than or equal to 0.01 and smaller than or equal to 0.15, y is more than or equal to 0.01 and smaller than or equal to 0.15, x is equal to y, and A and B are divalent metal ions. The preparation method comprises the following steps of firstly preparing nanoscale Mn[1-y]ByO from divalent manganese source and a compound containing metallic element B; preparing paste from a phosphorus source, a lithium source and a compound containing metallic element A and nanoscale Mn[1-y]ByO; and finally roasting the paste under the protection of argon or nitrogen, ball-milling, introducing C1-4 n-alkane gas at 400-600 DEG C to obtain the Li and Mn codoped manganese phosphate Li[1-x]AxMn[1-y]ByPO4/C. Through the Li and Mn codoping, the electrical conductivity in the material can be improved effectively, and the carbon layer covering the surfaces of particles is uniform and sufficient. The synthetic material has a relatively good discharge performance and cycling stability, the process is simple, the cost is low, and the material can meet the green chemistry development requirement.

The invention discloses a preparation method of a special antibacterial wool fiber for a wool hat. The preparation method comprises the steps of dipping the wool fiber in acetone, airing after washing, adding into a mixed aqueous solution of sodium cyanate and hydrogen peroxide, airing after dipping, and irradiating through an ultraviolet light to obtain a pretreated wool fiber; adding thiourea, urea and butyl titanate into absolute ethyl alcohol for mixing, adjusting a pH value, adding deionized water for stirring until a Tyndall effect occurs, standing for ageing, drying, grinding, and calcining to obtain modified nanometer titania; adding chitosan into an acetic acid aqueous solution, adjusting a pH value, adding the modified nanometer titania, adjusting a system pH value, adding glutaraldehyde after temperature rising, standing for reacting, centrifuging, washing, and drying to obtain modified chitosan; adding the modified chitosan, a plant extract, beta-cyclodextrin and a silane coupling agent KH-550 into the deionized water, and stirring to obtain an antibacterial solution; adding the pretreated wool fiber into the antibacterial solution for padding processing, and baking after drying.

The present invention relates to a tin-antimony oxide conducting film and its production method. Said film contains (wt%) 80%-96% of tin dioxide and 4%-20% of antimony pentoxide, their grain size diameter is 10-20 nm, and thickness is 80-180 nm. Its production method uses aqueous solution of SnCL4 and SbCL3 ethyl alcohol solution as raw material and includes the following steps: using amkmonia water to make precipitation, using oxalic acid and ammonia water to make back-solvation, concentration, preparing sol-gel, ageing, high-temp. spraying on silex glass for tin-antimony oxide conducting film with high conductivity and light transmittance, and high heat exchange efficiency.

The invention discloses a preparation method of a novel orientated silver ion doped titanium dioxide/graphene oxide composite material and application of the material in photocatalytic degradation. According to the method, graphene oxide-multiwalled carbon nanotubes are adopted as a carrier to perform functionalized modification on titanium dioxide on the surface of the carrier. The preparation method is characterized by comprising the following steps: adding ferroferric oxide, graphene oxide, multiwalled carbon nanotubes and tetrabutyl titanate according to a certain ratio to prepare magnetic titanium dioxide-graphene oxide-multiwalled carbon nanotubes, and further doping silver ions, thereby obtaining the magnetic titanium dioxide-graphene oxide-multiwalled carbon nanotube composite material in which silver ions are doped in an orientated manner. The catalyst has a remarkable degradation effect on polluted sewage of an azo structure, and has the advantages of being liable to separate, recycle and the like, and the degradation rate of the catalyst under visible light can be 90% or above.

The invention provides an anti-fog self-cleaning film and a method for preparing the same. The film is characterized in that: Fe2O3, SiO2 and TiO2 are mixed to form a ternary inorganic nanometer composite sol according to the molar ratio of (0.1-0.4):(10-40):100, and a water soluble macromolecular substance of which the molecular weight is between 400 and 10,000 is added to the composite sol according to the concentration of (0.1-4.0)g.L. The anti-fog self-cleaning film can achieve the advantages of super-hydrophilicity, strong hydrophilic retention capability, high transmittance, high photocatalytic activity, high capability of adhering to base materials, and good anti-fog self-cleaning effects.

The invention relates to a method for preparing Al mixed with ZnO nanosheet array by adopting a pulsed electromagnetic field, which is as follows: an FTO conductive sheet glass is placed in an ultrasonic cleaner for cleaning; the mixed solution I of zinc acetate, ethanol amine and ethylene glycol monomethyl ether is dripped on the conductive sheet glass, and is uniformly coated through a spin coater and heat treated to form a ZnO film thereon; the FTO conductive sheet glass coated with the ZnO film is put into a reaction kettle, the mixed solution II formed by aluminium nitrate, zinc nitrate and hexamethylene tetramine as well as deionized water is filled into the reaction kettle, the pulsed electromagnetic field treatment is applied to the reaction system in the reaction kettle, the kettle is moved to a constant temperature oven for hydrothermal reaction after the treatment, and the sediment on the surface of the glass is washed and dried after the hydrothermal reaction, so as to obtain the Al mixed with ZnO nanosheet array. The method is simple to operate, has low energy consumption, enables the orientation of the nanosheets to be identical, has higher verticality, enables the nanosheets to be neatly arrayed, has big specific surface area, facilitates electron transport when serving as the photoanode, and improves the efficiency of the dye sensitized solar cell.