130 results about "Tungsten trioxide" patented technology

The invention discloses a method for preparing a single-layer tungsten diselenide nanoband based on a space confinement strategy. By changing the flow and the growth time of hydrogen, effective control on the width and the thickness of a nanoband can be realized. The method comprises the following steps: uniformly spraying tungsten trioxide powder to one substrate, then covering the substrate by the other substrate, and forming micro reaction space which is of a 'sandwich'-like structure. Growth of a tungsten diselenide nanoband is carried out by utilizing a constant-pressure chemical vapor deposition method; physicochemical characteristics of a one-dimensional transition metal chalcogenide strongly depend on suspension key types on the edge of the one-dimensional transition metal chalcogenide, metallic properties are displayed by an ultranarrow band, and conversion from the metallic properties to semiconductor properties can be displayed from the edge to the center of a wider band; the tungsten diselenide nanoband is widely applied to micro-nano photoelectric devices due to the special property; industrial production of the tungsten diselenide nanoband can be realized through an experimental method of the invention.

The invention provides a rapid preparation method of tungsten trioxide, which specifically comprises the following steps: step 1, weighing crude tungstic acid, dissolving in ammonia water, heating and stirring to obtain an ammonium tungstate solution; step 2, slowly dropwise adding the ammonium tungstate solution in the step 1 into a poor solvent to obtain an ammonium paratungstate suspension, and step 3, filtering the ammonium paratungstate suspension in the step 2 to obtain an ammonium paratungstate filter cake, and leaching the ammonium paratungstate filter cake with the poor solvent; 4, the ammonium paratungstate filter cake in the step 3 is placed in a drying oven to be dried; and (5) roasting the ammonium paratungstate filter cake in the step (4) at high temperature to obtain a faint yellow irregular flaky tungsten trioxide product. According to the preparation method, a mixed solvent crystallization and high-temperature roasting two-step process is adopted, the solubility of ammonium tungstate in water is reduced by adding a poor solvent, so that an ammonium tungstate solution rapidly reaches a saturated state and is separated out, the crystallization process of ammonium paratungstate is accelerated, and the preparation speed and the crystallization rate of a tungsten trioxide product are high.

The invention discloses a modified lithium-rich manganese-based positive electrode material and a preparation method thereof, a pole piece and a battery, and the preparation method comprises the following steps: S1, mixing a lithium-rich manganese-based material with tungsten trioxide, and calcining for the first time to obtain an LRM-coated WO3 material; and S2, mixing the LRM-coated WO3 material with aluminum fluoride, and carrying out secondary calcination to obtain the modified lithium-rich manganese-based positive electrode material. According to the scheme, the modified lithium-rich manganese-based positive electrode material is prepared through combination of chemical bond regulation and phase structure design, the problem that the high-temperature performance of a traditional lithium-rich manganese-based material is degraded is solved, and a new thought is provided for development of a high-energy-density lithium ion battery.

The invention discloses a method for preparing a tungsten trioxide low-platinum electrocatalyst with a core-shell structure through pulse Joule heating, and belongs to the field of electrochemical catalysts for electrolysis of water. The invention aims to solve the problems that controllable amorphization is difficult to realize on the WO3 surface and a crystal nucleus-amorphous shell composite structure cannot be effectively constructed in the prior art. The preparation method comprises the following steps: 1, preparing a tungsten trioxide carrier with a core-shell structure; and 2, loading a platinum source. The method is used for preparing the tungsten trioxide low-platinum electrocatalyst with the core-shell structure through pulse Joule heating.

The invention discloses a surface plasmon resonance (SPR) hydrogen sensor based on an Ag / PDMS / Pt-WO3 multilayer structure. The SPR hydrogen sensor is characterized by comprising a halogen lamp light source, two sections of multimode optical fibers, a spectrometer and an SPR hydrogen sensing head, wherein the SPR hydrogen sensing head is composed of a different-core structure formed by multimode-single-mode-multimode optical fibers, a silver film, PDMS (polydimethylsiloxane) and Pt-WO3 (platinum-tungsten trioxide). The SPR hydrogen sensor based on the Ag / PDMS / Pt-WO3 multi-layer structure, which is simple to prepare, high in sensitivity and capable of being repeatedly used for a long time, is provided aiming at the defects that an existing optical fiber SPR hydrogen sensor is low in sensitivity and complex in device manufacturing, and PdH is changed from an alpha phase to a beta phase when Pd is used as a hydrogen sensitive material, so that the use of the device is influenced, and the like. When the hydrogen concentration is increased, the Pt-WO3 reacts with the hydrogen to generate heat, so that the refractive index of the PDMS film is changed, the SPR resonance spectrum is moved, and the hydrogen concentration is obtained by observing the offset of the PDMS film. The high refractive index sensitivity of SPR is brought into full play by utilizing the high refractive index change of PDMS, so that high-precision detection of hydrogen leakage is realized.

The invention discloses a width gradient tungsten disulfide nanobelt, a preparation method thereof and an application of the width gradient tungsten disulfide nanobelt in a self-driven photoelectric detector, a Ni film is deposited on a substrate and is annealed to form catalytic particles, and a chemical vapor deposition system is utilized to accurately control the temperature gradient between tungsten trioxide in a central temperature zone and a growth substrate in a downstream temperature zone, so that the width gradient tungsten disulfide nanobelt is obtained. And the solid sulfur source is propelled at a constant rate, the dynamic change of the sulfur / tungsten atomic ratio in the reaction environment is regulated and controlled, and a growth mode is guided to be converted from a gas-liquid-solid mechanism to a gas-solid mechanism, so that controllable preparation of the tungsten disulfide nanobelt with the width continuously and progressively decreased in the axial direction is realized. The width of the nanobelt gradually changes from 150-500 nm to 50-120 nm, the length of the nanobelt reaches 3-12 [mu] m, and the nanobelt has an armchair edge and a 3R phase stacking structure. A self-driven photoelectric detector constructed based on the nanobelt realizes high-sensitivity detection of 532 nm laser under zero bias voltage, the responsivity reaches 5.04 A / W, the detectivity reaches 3.23 * 10 < 12 > Jones, and the nanobelt shows important application value in the fields of optical signal detection, optical switches and wireless optical communication.

This invention belongs to the field of target material preparation technology, and discloses a sintering method for a yellow tungsten oxide titanium target and the yellow tungsten oxide titanium target itself. The sintering method for the yellow tungsten oxide titanium target includes the following steps: Step 1: Heating the tungsten oxide titanium target blank to 800℃ at a heating rate of 0.5-1℃ / min, with continuous oxygen flow during the process at an oxygen flow rate of 15-20L / min; Step 2: Heating from 800℃ to 1150℃-1200℃ at a heating rate of 2-3℃ / min, holding at this temperature for 1-3 hours, with continuous oxygen flow during the process at an oxygen flow rate of 40-60L / min. This invention discloses a sintering method for a yellow tungsten oxide titanium target, employing a two-stage heating approach. In the first stage of heating, a lower heating rate and lower oxygen flow rate are used to improve the density of the target material; in the second stage of heating, a higher heating rate and higher oxygen flow rate are used to avoid deactivation of tungsten trioxide, which could lead to a change in the valence of tungsten.

The invention discloses a preparation method of a high-sensitivity room-temperature flexible hydrogen sulfide gas sensor, which comprises the following steps: preparing a laser-induced graphene interdigital electrode in one step by using a carbon dioxide laser, depositing tungsten trioxide microspheres on the surface of LIG by using a film pressing technology so as to construct the hydrogen sulfide gas sensor, and forming a P-N heterojunction with the LIG, thereby obtaining the high-sensitivity room-temperature flexible hydrogen sulfide gas sensor. The response amount of the sensor is greatly improved through the heterojunction structure, the theoretical detection limit is as low as 774 ppt, and the actual detection limit is 3 ppb. The preparation method of the high-sensitivity room-temperature flexible hydrogen sulfide gas sensor provided by the invention has the advantages of high sensitivity, working at room temperature, low detection limit and long-term stability of more than seven months, and can be widely applied to the field of wearable gas monitoring.

The invention discloses a p-type tungsten disulfide nanotube bundle, a preparation method thereof and application of the p-type tungsten disulfide nanotube bundle in a photoelectric detector with adjustable light response linearity, and the method comprises the following steps: depositing an Au film on a SiO2 / Si substrate, and carrying out annealing to form a zero-dimensional Au nanoparticle catalytic layer; the method comprises the following steps: respectively placing tungsten trioxide (WO3) powder and sulfur (S) powder in different areas of a single-temperature-area tubular furnace, heating to 850-1000 DEG C in an Ar / H2 mixed gas low-pressure atmosphere, and reacting to generate a WS2 nanotube bundle with a multi-wall hollow structure; the obtained material has a cluster-shaped morphology in dense interlaced distribution, and shows stable p-type conductive characteristics. A photoelectric detector prepared based on the material has high responsivity (2.7 * 10 < 4 > A / W), high detection rate (1.6 * 10 < 13 > Jones) and quick response (15 ms) in a wave band of 375-1550 nm, and keeps stable performance in a range of 10-300 K. The method is simple in process, the growth process of the tungsten disulfide nanotube bundle can be accurately controlled, the polarity of tungsten disulfide is changed to be p-type, and large-scale preparation can be achieved.

The application discloses a nickel-based flux-cored wire and a preparation method and application thereof. The nano tungsten trioxide is introduced into the nickel-based flux-cored wire, the high-temperature strength and hot strength of the nickel-based alloy are improved, meanwhile, the hardness, friction performance and corrosion resistance of the alloy are improved, and the problems of low high-temperature corrosion strength, hot strength and mechanical performance of the nickel-based flux-cored wire are solved.

The application relates to a preparation method of Mg and W double-element co-modified ultra-high-nickel binary positive electrode material, in particular to Mg and W double-element co-modified high-nickel binary positive electrode material. 0.01 (Ni x Mn y )W z O2, wherein x the value of x is 0.9-0.95, y the value of y is 0.05-0.1, z the value of z is 0.003-0.006. The method comprises the following steps: (1) preparing a nickel and manganese metal salt aqueous solution, a mixed alkali aqueous solution and a reaction bottom solution; (2) respectively adding the metal salt aqueous solution and the mixed alkali aqueous solution into the bottom solution at a certain flow rate to perform a constant-temperature precipitation reaction in a nitrogen atmosphere; (3) after the precipitation reaction is completed, cooling to room temperature, filtering, washing and drying the precursor; (5) after the dried precursor is mixed with metered lithium salt, magnesium oxide and tungsten trioxide, high-temperature solid-phase reaction is performed in an oxygen atmosphere to obtain the Mg and W double-element co-modified ultra-high-nickel binary positive electrode material. The Mg and W double-element co-modified high-nickel binary positive electrode material prepared by the method has a specific capacity of 179.19 mAh / g after 100 cycles at a 0.5C rate, a capacity retention rate of 93.1% or above, and good cycle and rate performance.

A negative electrode material is a negative electrode material for a battery, and the material includes carbon, tungsten trioxide formed on the surface of the carbon, and silicon formed on the surface of the carbon.

A thin-film photovoltaic module with dimming function and its preparation method, belonging to the field of photovoltaic power generation, includes transparent conductive glass, an electron transport layer, a semi-transparent perovskite light-absorbing layer, a hole transport layer, an electrode layer, a dimming film layer and a metal oxide conductive layer stacked in sequence on the transparent conductive glass; the dimming film layer adopts a liquid crystal layer and / or a tungsten trioxide layer; this solution integrates two dimming function layers, the liquid crystal layer and the tungsten trioxide layer, and can control the transparency of the two dimming layers separately or jointly by adjusting the temperature of the liquid crystal layer or applying an external electric field to it, and applying an external electric field to the tungsten trioxide layer, thereby achieving more precise light transmittance adjustment.

The invention discloses an amorphous electrochromic film inlaid with Cs-doped tungsten trioxide quantum dots as well as a preparation method and application of the amorphous electrochromic film. The preparation method comprises the following steps: S1, adding hydrochloric acid into a sodium tungstate dihydrate aqueous solution to obtain a precipitate; washing the precipitate until the pH value of the supernate is greater than 3, and then drying the precipitate to obtain hydrated tungstic acid powder; dissolving hydrated tungstic acid powder in a hydrogen peroxide solution to obtain a peroxy tungstic acid solution, and then adding a substance containing a Cs element to obtain a Cs-peroxy tungstic acid solution; the molar ratio of Cs ions to W ions in the Cs-peroxotungstic acid solution is not less than 1: 100 and less than 5: 100; s2, heating, evaporating and concentrating the Cs-peroxy tungstic acid solution to obtain a precursor solution containing a bimetal oxygen cluster; and transferring the precursor solution containing the bimetal oxygen clusters to a substrate by adopting a film coating process, and annealing to obtain the amorphous tungsten trioxide electrochromic film inlaid with the Cs-doped tungsten trioxide quantum dots.

The invention discloses a tungsten nitride / carbon composite material as well as a preparation method and application thereof. The preparation method adopts a molten salt synthesis method and takes tungsten trioxide as a tungsten source, thiourea as a nitrogen source and a sulfur source, melamine resin as a carbon source and sodium chloride as a molten salt template. Under the room temperature condition, powder obtained through ball milling is subjected to high-temperature roasting through a tubular furnace to prepare the tungsten nitride and carbon composite material, and the pore channel structure and the heteroatom content of the material can be adjusted by controlling the proportion of precursors. The product yield of the method reaches 16%, and the material can be used as the water electrolysis hydrogen production catalyst, and is a very ideal method for preparing the water electrolysis hydrogen production catalyst.

The invention belongs to the technical field of target materials, and particularly relates to a tin oxide-based composite target material and a preparation method thereof. The tin oxide-based composite target material provided by the invention comprises tin oxide, doped oxides and sintering aids, the doped oxides are antimony pentoxide, vanadium pentoxide, nickel oxide and tungsten trioxide, and the sintering aids are magnesium oxide and yttrium oxide. The antimony pentoxide, the vanadium pentoxide, the nickel oxide and the tungsten trioxide are used as doped oxides, so that the electrical and optical properties of the target material are effectively improved; magnesium oxide and yttrium oxide are adopted as sintering aids, grains are refined, and the compactness and the mechanical property of the target material are improved; atomic-scale mixing of part of elements is achieved through a sol-gel method, then atomic-scale doping is conducted through a high-energy ball milling method, the distribution deviation of the elements in a matrix is reduced, sintering is conducted through a discharge plasma furnace, and the volatilization loss of the elements and the pore defect in the target material are reduced.

The invention belongs to the technical field of recycling of rare and noble metal secondary resources, and discloses a method for preparing a tungsten compound and chloroplatinate from a waste catalyst and application of the method. The method comprises the following steps: (1) firing and crushing the waste catalyst, (2) reacting the waste catalyst with acid, (3) filtering and discarding filtrate, (4) reacting the precipitate with ammonia water, filtering to obtain an ammonium tungstate solution, and retaining filter residues; (5) concentrating the ammonium tungstate solution, crystallizing, separating and drying to obtain an ammonium paratungstate finished product; and (6) reacting the filter residues retained in the step (4) with aqua regia to prepare chloroplatinate. And (7) firing the ammonium paratungstate at a high temperature to obtain tungsten trioxide. According to the method, tungsten and platinum can be effectively separated from the carrier, and the recovery rate of rare and precious metals is increased.

The present invention provides a method for preparing a fluorine adsorbent, which uses tungsten trioxide, ammonium metatungstate, and water glass as raw materials, obtains a granular substrate after granulation and sintering, then performs a primary modification with a phosphoric acid solution, and after drying, performs a secondary modification with an aluminum chloride aqueous solution, and obtains a fluorine adsorbent after washing and drying. The present invention also provides the use of the adsorbent obtained by the above preparation method in removing fluoride ions from water. The present invention utilizes Al4(PO4) x (OH) 12‑3x The material's rapid adsorption capacity for fluoride ions enables it to quickly capture fluoride ions in water, ensuring that the fluoride ion concentration in the produced water meets the standard. It has the ability to adsorb fluoride ions in large capacity, which can reduce the number of regenerations and increase the adsorption capacity and water treatment volume of the adsorbent per unit volume.

The invention belongs to the technical field of tungsten powder preparation, and particularly relates to medium-particle tungsten powder and a preparation method thereof.The preparation method comprises the following steps that tungsten trioxide powder with the Fisher particle size being 3-6 m, the specific surface area being 4.5-8.5 m < 2 > / g and the apparent density being 1.5-2.2 g / cm < 3 > is obtained; the method comprises the following steps: respectively reducing tungsten trioxide powder by adopting hydrogen at 650-700 DEG C, 800-850 DEG C and 1000-1050 DEG C, and sieving to obtain the medium-particle tungsten powder. According to the method, the low-apparent-density tungsten oxide powder is selected, and staged heating reduction is adopted, so that the hydrogen utilization rate can be increased, the oxygen content in tungsten oxide is reduced, and the tungsten oxide is reduced more thoroughly; by controlling the low hydrogen flow, the hydrogen return pressure and the dew point, it is ensured that tungsten oxide is thoroughly reduced, the volatilization deposition effect is remarkable, and the tungsten powder is complete in development, regular in shape and free of fine agglomerated particles which are not thoroughly reduced or high in oxygen content.

SOLUTION: A substrate; a photovoltaic module comprising a plurality of photovoltaic cells disposed on the substrate; top and bottom electrodes incorporated into the photovoltaic module, the top and bottom electrodes being at least partially exposed; and a protective encapsulant covering at least an active area of the photovoltaic module, the photovoltaic device wherein the protective encapsulant comprises a) at least one vacuum-processed material having a deposition temperature of 1200 °C or less, or b) at least one solution-processed metal oxide selected from molybdenum oxide (MoOx), tungsten trioxide (WO3), vanadium pentoxide (V2O5), zinc oxide (ZnO), nickel oxide (NiOx), and titanium dioxide (TiO2).EFFECT: The protective encapsulant of the present disclosure can eliminate the reaction of the photovoltaic layer with air, and thus can improve the lifetime of the photovoltaic module.SELECTED DRAWING: Figure 1

The invention belongs to the technical field of spherical tungsten carbon compound preparation, and particularly relates to a spherical tungsten carbon compound and a preparation method and application thereof.The preparation method of the spherical tungsten carbon compound comprises the following steps that S1, raw materials are obtained, and the raw materials comprise 71 wt%-76 wt% of tungsten carbide powder, 18 wt%-23 wt% of tungsten powder and 5 wt%-7 wt% of tungsten trioxide; s2, carrying out ball milling on the raw materials to obtain ball-milled slurry; and S3, the ball-milled slurry is subjected to spray drying, then high-temperature carbonization is conducted at the temperature of 1600-1800 DEG C, and the spherical tungsten-carbon compound is obtained. The spherical tungsten-carbon compound is prepared through a powder metallurgy method, has high hardness and has high apparent density after being crushed and sieved, and the spherical tungsten-carbon compound has the advantages of being high in mechanical strength, good in mechanical property and good in mechanical property. The coating with relatively high wear resistance can be prepared by adopting laser cladding or plasma surfacing.

The invention discloses an easy-to-clean dust cup of a dust collector, and belongs to the technical field of cleaning electric appliances, the easy-to-clean dust cup comprises a dust cup body, the surface of the dust cup body is provided with a nano antifouling coating, and the nano antifouling coating is sprayed on the dust cup body. The nano antifouling coating is composed of nano silicon dioxide doped with nano tungsten trioxide and nano tin oxide. Compared with the prior art, the nano antifouling coating is additionally arranged inside and outside the dust cup, can form a fine protective film on the surface of the dust cup, has a self-repairing function, and can inhibit static electricity on the surface of a base material, so that stains are not easily attached to the surface of the base material, and the attached stains can be self-cleaned even if encountering water; and the cleanness of the dust cup is always kept.

The invention provides a process for preparing molybdenum and tungsten oxyhalide compounds which are useful in the deposition of molybdenum and tungsten containing films on various surfaces of microelectronic devices. In the process of the invention, a molybdenum or tungsten trioxide is heated in either a solid state medium or in a melt-phase reaction comprising a eutectic blend comprising alkaline and / or alkaline earth metal salts. The molybdenum or tungsten oxyhalides thus formed may be isolated as a vapor and crystallized to provide highly pure precursor compounds such as MoO2Cl2.

The invention belongs to the technical field of catalyst materials, and particularly relates to an oxygen-deficient tungsten oxide / triazine skeleton catalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out cycloaddition reaction on 4, 4 '-biphenyl dinitrile and dicyandiamide, then carrying out thermal polymerization reaction with dicyandiamide, and carrying out high-temperature calcination to obtain a covalent triazine skeleton; the preparation method comprises the following steps: by taking sodium tungstate dihydrate as a tungsten source and citric acid and glucose as surfactants, carrying out hydrothermal reaction to obtain a tungsten trioxide precursor, then carrying out first-time calcination in an inert atmosphere, and then carrying out second-time calcination in an oxidizing atmosphere to obtain the oxygen vacancy doped tungsten trioxide nanosheet. And carrying out self-assembly on the covalent triazine skeleton and the oxygen vacancy doped tungsten trioxide nanosheet in water to prepare the oxygen vacancy tungsten oxide / triazine skeleton catalyst. According to the invention, an S-type heterojunction catalyst of WO3 with controllable oxygen vacancy concentration and biphenyl-type COF is constructed, and efficient one-step double-electron photocatalysis ORR for preparing H2O2 is realized.

The application belongs to the technical field of target materials, and particularly relates to a tin oxide-based composite target material and a preparation method thereof. The tin oxide-based composite target material provided by the application comprises tin oxide, doped oxide and sintering aid, the doped oxide is antimony pentoxide, vanadium pentoxide, nickel oxide and tungsten trioxide, and the sintering aid is magnesium oxide and yttrium oxide. The application uses antimony pentoxide, vanadium pentoxide, nickel oxide and tungsten trioxide as the doped oxide, effectively improves the electrical and optical properties of the target material; uses magnesium oxide and yttrium oxide as the sintering aid, refines the grains, and improves the density and mechanical properties of the target material; uses the sol-gel method to realize atomic-level mixing of part of elements, then uses the high-energy ball milling method to realize atomic-level doping, reduces the distribution deviation of the elements in the matrix, uses the discharge plasma furnace to realize sintering, and reduces the volatilization loss of the elements and the pore defects in the target material.

This invention discloses a sunflower-shaped tungsten oxide / indium zinc sulfide heterojunction. The tungsten oxide / indium zinc sulfide heterojunction consists of tungsten trioxide located within a central sphere and indium zinc sulfide distributed as nanosheets on the sphere's surface, forming a three-dimensional sunflower shape. Using glucose as a raw material, this invention first prepares uniformly sized carbon spheres via a hydrothermal method. Then, using the synthesized carbon spheres as a template and WCl6 as a precursor, hollow WO3 spheres are obtained through in-situ hydrolysis combined with high-temperature calcination. Finally, using the synthesized hollow WO3 spheres, indium chloride, indium chloride, and thioacetamide as starting materials, the three-dimensional sunflower-shaped tungsten oxide / indium zinc sulfide heterojunction is prepared using a water bath method. The WO3 / ZnIn2S4 heterojunction material of this invention has a larger specific surface area than pure WO3, which is beneficial for exposing more active sites. The three-dimensional heterojunction constructed in this invention can effectively inhibit the free diffusion of CO2 molecules, increase the local CO2 concentration on the catalyst surface, and is more conducive to the adsorption and activation of CO2 molecules.

The invention discloses a bionic super-hydrophobic composite structure with an all-weather deicing function and a preparation method of the bionic super-hydrophobic composite structure. The preparation method comprises the steps that S1, a base body is provided, and a bionic super-hydrophobic structure is prepared on the base body through a selective laser melting forming method by means of iron-based amorphous alloy powder; the surface of the bionic super-hydrophobic structure is covered with a micron-sized mastoid structure; s2, forming a nano-scale tungsten trioxide film on the surface of the bionic super-hydrophobic structure through magnetron sputtering, so as to obtain a composite structure with micro-nano dual-scale roughness; s3, the composite structure is annealed, and the bionic super-hydrophobic composite structure with the all-weather deicing function is obtained; wherein the annealing condition is set as follows: crystallization of the iron-based amorphous alloy is avoided, and the tungsten trioxide film is fully crystallized. According to the invention, the combination of passive ice suppression and active deicing is successfully realized on one structure.

The present application relates to a kind of photocatalytic methane conversion preparation formic acid method, the method includes the following steps: ultrasonic uniform mixing palladium supported photocatalyst with solvent, then oxygen and methane are successively introduced, and methanol, formaldehyde, methyl hydroperoxide and the formic acid obtained by reaction under irradiation;The palladium supported photocatalyst includes palladium active component and tungsten trioxide carrier.The present application uses methane as raw material, oxygen as oxidant, under the joint action of illumination and palladium supported photocatalyst, methane is converted into formic acid, and the obtained formic acid has higher yield and selectivity;The reaction condition of photocatalytic methane conversion system into formic acid is mild, process is simple and green environmental protection, suitable for large-scale industrial production.

The invention belongs to the technical field of rare metal hydrometallurgy, and particularly relates to a method for deeply removing tungsten and molybdenum in a copper sulfate solution. According to the method, a copper sulfate solution and a sulfur source are mixed for a tungsten-molybdenum precipitation reaction, precipitation residues and impurity removal liquid are obtained after solid-liquid separation, and the copper sulfate solution contains tungsten-molybdenum impurities; the impurity removal liquid is subjected to adsorption deep impurity removal through ion exchange resin, a pure copper sulfate solution is obtained, the concentration of tungsten trioxide in the pure copper sulfate solution is smaller than or equal to 10 mg / L, and the concentration of the molybdenum element is smaller than or equal to 10 mg / L. According to the method provided by the invention, deep removal of tungsten and molybdenum in the copper sulfate solution is realized, and the tungsten and molybdenum concentrations in the copper sulfate solution can be reduced to 10 mg / L or below; meanwhile, the method provided by the invention does not use dangerous chemical reagents, is environment-friendly, lays a foundation for subsequent preparation of high-purity copper products, and is more suitable for industrial application.

This invention discloses a method for preparing a hydrophobic modified photocatalytic-radiative cooling Janus composite membrane and its application, belonging to the fields of functional membrane materials and optoelectronic environmental protection technology. The Janus composite membrane uses polyethylene terephthalate (PET) film as a substrate, with a modified photocatalytic layer and a radiative cooling layer respectively disposed on both sides. The surface is hydrophobically modified with hexadecyltrimethoxysilane (HDTMS). The photocatalytic layer is composed of nitrogen-doped titanium dioxide, tourmaline powder, tungsten trioxide, and acrylic resin, and can catalytically degrade PM2.5 particles and the organic pollutants they carry. The radiative cooling layer is composed of micro / nano silica, hexagonal boron nitride, and alumina particles combined with resin, and can reduce the membrane surface temperature at night through radiative cooling, inducing the condensation of ambient water vapor. This invention adopts a Janus structure design with dual-sided discrete and collaborative operation, which combines the functions of photocatalytic degradation of organic pollutants, dust blocking of particulate matter, and day and night self-cleaning. It has the advantages of simple structure, no additional energy consumption, high functional integration and good long-term stability, and can be widely used in scenarios such as PM2.5 particulate dust blocking, photocatalytic degradation of organic pollutants and water purification.