126 results about "Light Activity" patented technology

The present invention relates to the preparation process of TiO2 sol with relatively high visible light activity. TiO2 sol has high dispersivity, homogeneous granularity and other advantages, and may be modified via adding RE or other transition metals to alter its energy band structure and to form photocatalytic TiO2 material capable of being excited with visible light. The present invention has improved technological process of preparing TiO2 sol, and through synthesis at low temperature and normal pressure and doping with RE or other transition metals, TiO2 sol with greatly raised visible light activity is prepared. The present invention may be applied in processing polluted atmosphere, purifying indoor air, sterilizing indoor air, sterilizing crop, etc. and has important application foreground.

The invention provides a preparation method of nanocluster mimic enzyme with visible-light activity and a use of the nanocluster mimic enzyme in colourimetry detection of trypsin. Gold/silver nanoclusters modified by bovine serum albumin and mercaptosuccinic acid as surface modification agents has peroxidase-like catalytic characteristics under visible light irradiation and can catalyze chromogenic substrate oxidation. Compared with the peroxidase, the nanocluster mimic enzyme with visible-light activity is free of a high-concentration oxidizing agent and has high catalytic activity, good stability and eco-friendly catalytic conditions. Trypsin decomposes a protein template on the surface of the nanocluster so that the nanocluster surface state is changed and causes aggregation thereby reducing catalytic activity. The preparation method has a trypsin detection linear range of 9.0*10<-7> to 1.0*10<-3>g/mL and has a detection limit of 0.6 micrograms per milliliter far lower than trypsin content of urine and blood of patients.

The invention proposes a kind of hydrothermal method used for preparing light catalyzing material with visible light active nano crystal Bi2WO6 powder. The method makes bismuth nitrate and sodium tungstate as raw materials, prepare them into mixed solution, then add into reacting kettle and have hydrothermal treatment for 10 - 48 hours at 100 - 200 Deg. C, take out reacting kettle, after the system cooled to room temperature, repeatedly wash the got output to neutral with deionized water, then dry in vacuum condition, finally through 100 -1000 heat treatment for 0.5 -10 hours, we can obtain light catalyzing material with visible light active nanometer crystal Bi2WO6 powder. The method has such advantages as low synthesizing temperature, large specific surface area of obtained simples and small grains. The prepared material can not only show light catalyzing activeness in ultraviolet, but also show light catalyzing activeness in visible light bound as sunlight or indoor lamplight.

The invention provides a method for preparation of photo-catalytic nitrogen doped nano titanium oxide having visible light activity, belonging to the art of preparing titanium oxide powder. With directive thermal treatment, mix nano TiO2 powder, TiO2 colloid or Ti (OH) 4 with nitrogen source and water proportionally to prepare mixture suspension, mix around for among 0.5- 1h in among 10- 30Deg. C, dry for among 30- 90Deg. C, thermally treat for among 300- 650Deg. C and keep 0.5- 6h, then the anatase- type nitrogen doped nano titanium oxide powder is prepared. The merit is characterized in that: the property simulation of the prepared anatase- type nitrogen doped nano titanium oxide powder contains: measuring the phase constituent and the grain size number by X- ray diffraction, measuring light absorption by ultraviolet- visible light defuse reflection. measuring the absorption spectrum of photodegradation methyl blue solution with ultraviolet- visible light spectrophotometer.

A method for using ultrasonic mixing to prepare Ag-g-C3N4/TiO2 photocatalyst is characterized by including: heating reagent melamine to 540 DEG C to allow the same to split into g-C3N4; using ultrasonic mixing to allow P25 to load the g-C3N4; using solidifying sol process and silver-mixed synthesis to prepare the Ag-g-C3N4/TiO2 photocatalyst. Due to the fact that the Ag-g-C3N4/TiO2 photocatalyst is high in visible light activity, the photocatalyst can be served as a significant waste water processing agent with potential research value. The method is simple in reaction condition, mild and stable in reaction, and easy in mass production.

The invention relates to a method for preparing a Pt-C3N4-TiO2 three-component visible light photocatalyst. The method is characterized by comprising the steps of: firstly heating melamine up to the temperature of 540 DEG C so as to be cracked into graphite-like nitrogen carbide (g-C3N4); then carrying out ultrasonic mixing so as to enable P25 to be loaded with g-C3N4; and finally synthesizing by using an immobilized sol process, thereby preparing the target product. The composite photocatalyst with the structure has high visible light activity, thus the photocatalyst becomes an important sewage treatment agent with a potential research value. The method has the advantages that the reaction conditions are simple, the reaction is mild and stable, and the production enlargement is facilitated.

The invention relates a Bi2WO6 nano-fiber cloth and a preparation method and an application thereof. The nano-fiber cloth is characterized in that the nano-fiber is prepared from Bi2WO6 nano-fiber with a length of hundreds of microns and a diameter of 30-400nm by electrostatic spinning; wherein, a defined amount of reactants are mixed and stirred according to a stoichiometry ratio, then proper tackifier is added to obtain Bi2WO6 precursor with proper viscosity and charge quantity, and finally Bi2WO6 nano-fiber cloth with controllable size, crystal type and morphology can be obtained through the control of the proportioning of each material in the precursor solution and the conditions of the electrostatic spinning. The Bi2WO6 nano-fiber cloth prepared by the electrostatic spinning used as photocatalyst has high specific area and crystallinity so that the visible light activity of the cloth is high, a certain kind of organic pollutants can be degraded in short time, and meanwhile, the catalyst can be recycled and reused very conveniently so that the problem of practical application of photocatalyst is solved.

A preparation method of bismuth oxybromide with high-efficient visible light activities adopts cetyl pyridine bromide as raw material, the surfactant has the functions of providing bromine source and structure template agent simultaneously, and the bismuth oxybromide with stable structure and performance and high activity can be obtained. Dilute nitric acid solution dissolved with Bi(NO3)3 is dripped into the cetyl pyridine bromide solution to produce faint yellow precipitate, and then the pH value needs to be adjusted to 7; and the mass ratio of the two raw materials meets nBi: nBr=1: 1.5. The bismuth oxybromide synthesized by the method is faint yellow solid powder and has no special smell. The bismuth oxybromide has quadrangular crystal form detected by an instrument, the specific surface area is large, the surface aperture is small, the band gap is 2.62eV, the crystallinity is 98.3% of layer crystal, the product purity is more than 99.9%, the visible light activity of the prepared bismuth oxybromide is high, and various organic dyes and microcystic toxins can be degraded effectively in a short time.

The invention relates to the field of photocatalysis materials, in particular to a method for preparing a boron-doped titanium dioxide crystal containing a specific crystal plane. The method comprises the following steps of: loading titanium boride serving as a precursor into a reaction kettle of an acid solution containing different anions; sealing the reaction kettle; putting the reaction kettle into a baking oven for heating; taking a reaction sample out; washing with deionized water and drying to obtain a boron-doped titanium dioxide crystal containing a specific crystal plane in an acid system containing anions; and further thermally treating the boron-doped titanium dioxide crystal under different atmospheres, adjusting the distribution of boron in the crystal, and introducing a newheteroatom. In the invention, the boron-doped titanium dioxide crystal can be directly prepared by taking the titanium boride as the precursor and taking the anions as a morphology control agent, andthe surface of the boron-doped titanium dioxide crystal consists of an identifiable crystal plane, so that effective adjustment and control of the electronic structure of the photocatalysis material are effectively realized, and the defects of poor reaction selectivity and unavailable invisible light activity of the photocatalysis material are overcome.

The invention relates discloses a high-visible-light-activity sulfur-modified carbon nitride photocatalyst as well as a synthetic method and application of photocatalyst, relating to the technical fields of material preparation and photocatalysis and solving the problem of low activity of an existing graphite-phase carbon nitride catalyst caused by the low visible light absorption coefficient and the large electron hole recombination rate. The synthetic method comprises the following steps: (1) grinding melamine and sublimed sulfur, and uniformly mixing the melamine with the sublimed sulfur so as to obtain mixed powder; (2) filling a combustion boat with the mixed powder obtained in the step (1), putting the combustion boat into a tube furnace, heating the tube furnace from the room temperature to 550-650 DEG C according to a heating rate of 5 DEG C/minute-15 DEG C/minute in the presence of argon, keeping the temperature for 1-4 hours, and cooling the tube furnace to room temperature so as to obtain the sulfur-modified carbon nitride photocatalyst. The sulfur-modified carbon nitride photocatalyst disclosed by the invention can be applied to the fields of producing hydrogen by decomposing water by virtue of visible light and degrading pollutants.

The invention relates to a preparation method of a Ti<3+>-doped TiO2 composite graphene photocatalyst. Graphene oxide and gas-phase titanium dioxide (P25) are used as precursors to prepare the novel Ti<3+>-doped TiO2 composite graphene photocatalyst by a low-temperature vacuum activation method. Compared with the prior art, the invention can simultaneously implement Ti<3+> autodoping modification of TiO2 by one step, so that the photocatalyst has strong visible light response range; by carrying out reduction modification on the graphene oxide, the photocatalyst has higher electron transmission capacity; and the supporting modification is carried out on the graphene surface by using the TiO2 nanoparticles to generate a Ti-O-C chemical bond, thereby promoting the transfer of photoproduced electrons from TiO2 to the graphene surface. The prepared graphene-supported TiO2 photocatalyst has high ultraviolet and visible light activity, and also has high capacity for hydrogen production by composing water under visible light.

The invention discloses a method for peroxy titanic acid with visible-light activity for supported photocatalyst. Wherein, preparing clear solution with given concentration by TiSO4 to drip with diluted ammonia into deionized water with given pH value as basic solution; mixing and holding given pH value to form precursor deposition of titanium oxide; continuing to mix for some time; taking solid-liquid separation to the suspending liquid to clean for 3-5 times, dripping some H2O2 peptizer to deposite and obtain the product. The film coating can crystallize and form anatase phase at 150Deg. The membrane layer particle is 10-20 nano sphere or ~20X~100 nano column.

The invention discloses a process for preparing an oxidized graphene/titanium dioxide composite material with high visible-light activity at a low temperature, which aims to solve the problem that in the industrial application process of a nano titanium dioxide photo-catalytic oxidation technology, the visible light is low in utilization rate and easy to deactivate. According to the invention, by using the adjustability of the chemical doping diversities (varying with oxidation degrees) of oxygen-containing groups of oxidized graphene and the oxidation degree on the forbidden bandwidth of the oxidized graphene, the oxidized graphene/titanium dioxide composite material is prepared at a low temperature. The process disclosed by the invention is simple in whole synthetic process, convenient for operation, low in cost, and environment-friendly; and the prepared oxidized graphene/titanium dioxide composite material has high visible-light catalytic degradation activity, and the organic pollutant degradation capacity of the prepared oxidized graphene/titanium dioxide composite material is much higher than that of commercially-available photocatalysts at present.

The invention relates to a preparation method of a carbon and nitrogen modified nano-titanium dioxide thin film with visible light activity, which belongs to the field of nanotechnology. The preparation method comprises the following steps: 1) etching and cleaning the surface of metal titanium; 2) adopting hydrogen peroxide solution for oxidizing the surface of the metal titanium, thereby forming a peroxotitanium acid nano flower-like thin film; 3) adopting the hydrothermal method for forming a titanium dioxide nano-thin film; and 4) calcining in the urealysis atmosphere for forming a modified titanium dioxide nanowire thin film. The preparation method has the advantages of simplicity, easy operation and low cost and is applicable to large-scale industrial production, and the prepared modified titanium oxide thin film has the photocatalytic degradation capability to organic matters under the radiation of visible light.

A preparation method of a nitrogen-doped nanometer titanium dioxide loaded active carbon fiber composite material, concretely comprises the following steps: (1) preparing a mixture solution of absolute ethyl alcohol and water, adjusting the mixture solution by dilute nitric acid, so as to obtain a mixture solution A; (2) mixing tetrabutyl orthotitanate with absolute ethyl alcohol, so as to obtain a mixture solution B; (3) dropwise adding the mixture solution B into the mixture solution A, so as to obtain a mixture sol C; (4) adding an active carbon fiber into the mixture sol C, extruding the residual mixture sol C from the active carbon fiber after immersion; (5) drying the active carbon fiber containing the mixture sol C in a drying oven; and (6) placing the dry active carbon fiber into a N2 atmosphere furnace, and calcinating and crystallizing at 300-600 DEG C. The preparation method solves the problems that the visible light activity of the nano titanium dioxide is low, the titanium dioxide is easy to agglomerate in water and difficult to recover, and the active carbon fiber is easy to absorb and saturate, and repeated use effect is poor.

The invention provides a method, a device and a wearable device for monitoring the states of light activities. The method comprises the following steps: determining the activity amount of a user according to accelerated speed data in a plurality of axial directions collected within the set time period; if the activity amount is smaller than a first preset threshold value, determining the axial characteristic values of each axial direction according to the accelerated speed data of the plurality of axial directions, wherein the first preset threshold value is a positive number greater than 0; determining the characteristic values of the light activities within the set time period according to the axial characteristic values of each axial direction; and determining the states of the light activities of the user within the set time period according to the characteristic values of the light activities. With the adoption of the technical scheme of the invention, the states of the light activities of the user can be accurately determined, by monitoring the states of the light activities of the user in real time, the sleep state of the user can be accurately judged, and thus the reliability for monitoring the sleep quality of the user is improved.

The invention discloses a bismuth vanadate nanowire-graphene photocatalyst preparation method. The method includes: proportionally mixing bismuth salt, ammonium metavanadate and oxalate dihydrate into distilled water, and ultrasonically mixing to obtain mixed liquid; adding graphene oxide into the mixed liquid, and ultrasonically mixing to obtain a precursor; finally transferring the precursor into a high-pressure reaction kettle with a substrate to realize hydrothermal reaction, and cleaning and drying the product loading substrate after reaction is finished, so that a bismuth vanadate nanowire-graphene photocatalyst is obtained. The bismuth vanadate nanowire-graphene photocatalyst preparation method is technically simple in preparation, mild in reaction condition and short in reaction time, prepared bismuth vanadate nanowires and graphene can be closely contacted and compounded, separation of photo-induced electron holes is benefited, and accordingly photocatalysis efficiency is improved. The method is a high visible light activity photocatalyst preparation method low in production cost, simple and feasible.

The invention discloses a method for preparing sulfur-nitrogen co-doped nanometer titanium dioxide through a rapid sol-gel process. The method specifically comprises the following steps: step 1. preparing a sulfur-nitrogen co-doped nanometer titanium dioxide sol-gel precursor; step 2. adding deionized water into the sulfur-nitrogen co-doped nanometer titanium dioxide sol-gel precursor obtained in the step 1, stirring and standing to obtain wet gel; step 3. putting the wet gel obtained in the step 2 into a drying oven, drying at the temperature of 70-90 DEG C to obtain dried gel in which the solvent and moisture are removed; and step 4. sequentially grinding and calcining the dried gel obtained in the step 3 to obtain anatase type sulfur-nitrogen co-doped nanometer titanium dioxide. According to the method for preparing the sulfur-nitrogen co-doped nanometer titanium dioxide through the rapid sol-gel process, a sulfur-nitrogen co-doped nanometer titanium dioxide photocatalyst with visible-light activity can be prepared, a white flocculent is avoided in the gelling process, and the production cycle is shortened.

A photocatalyst according to the present invention has a structure in which the titanium dioxide doped with the transition metals is supported on the support such that a band gap thereof is low and a specific surface area thereof is high, thereby exhibiting an excellent photocatalytic activity even in a visible light region and providing an excellent effect of adsorbing an organic compound and removing the same even under a condition in which light is not emitted.