20results about How to "Improve visible light absorption" patented technology

The invention belongs to the field of polymer modification and processing, and particularly relates to a nano photocatalytic self-cleaning composite material, a fresh-keeping cover and a preparation method of the fresh-keeping cover. The composite material comprises aliphatic nylon, a maleic anhydride grafted copolymer, nano titanium dioxide, carbon nanotubes, boron nitride, a coupling agent, a release agent and an antioxidant. The nano photocatalytic self-cleaning composite material is prepared by taking nano titanium dioxide as an antibacterial active agent and adding a certain amount of carbon nanotubes and boron nitride powder. The carbon nanotubes can conduct electrons, have high surface area and high adsorption capacity, and are good dopants and carriers for titanium dioxide as photocatalysts. Hexagonal boron nitride can effectively improve separation and transfer of photo-induced electron-hole pairs of the material, so that the visible light response photocatalytic activity is enhanced. And by adding the carbon nanotubes and boron nitride, the dispersing performance of nano titanium dioxide can be physically improved, titanium dioxide agglomeration is prevented, and the photocatalytic self-cleaning performance of the nano titanium dioxide is improved.

The invention relates to the technical field of environmental chemistry and photoelectrocatalysis, in particular to a TiO2 / polyaniline organic-inorganic hybrid composite photoanode which is characterized in that a stainless steel sheet serves as a substrate of the composite photoanode, a TiO2 / polyaniline composite film layer serves as a surface layer of the composite photoanode, and TiO2 / polyaniline in the composite layer of the photoanode is combined with the stainless steel substrate through the action of a coalescing agent. The surface of the composite photoanode is smooth and flat, and the TiO2 / polyaniline composite photoanode is low in cost, small in chemical reagent danger, small in environmental harm and capable of enhancing visible light absorption, improving the absorption capacity of the composite anode in a visible light area and fully improving the utilization efficiency of solar energy. And moreover, the interfacial interaction between TiO2 and polyaniline can be beneficial to promoting charge separation, providing a more effective charge transmission channel and reducing charge recombination loss, so that the photoelectric conversion efficiency is improved.

The invention relates to a preparation method and application of an Ag-coated BiOI nanosheet array composite SERS (Surface Enhanced Raman Scattering) substrate. The preparation method comprises the following steps: preparing a bismuth oxyiodide (BiOI) nanosheet array through electro-deposition, sputtering silver nanoparticles to the surface of BiOI nanosheets to obtain an Ag-coated BiOI nanosheet composite array, and irradiating the Ag-coated BiOI nanosheet composite array by a xenon lamp to enhance SERS signals. During preparation, firstly, a large-area uniform BiOI nanosheet array is obtained on the surface of pretreated FTO conductive glass through an electro-deposition method, then silver nanoparticles are sputtered on the surfaces of BiOI nanosheets to obtain an Ag-coated BiOI nanosheet array composite substrate, and then the composite SERS substrate is soaked in a detection solution to adsorb detection molecules. Finally, the soaked Ag-coated BiOI nanosheet composite substrate is placed under a xenon lamp to be irradiated for a certain time, and then Raman detection is conducted. The adsorption capacity of the Ag-coated BiOI nanosheet composite substrate on target detection molecules can be remarkably improved through irradiation of a xenon lamp, so that SERS signals are improved, and the detection sensitivity is improved; the Ag-coated BiOI nanosheet composite substrate based on xenon lamp irradiation shows good SERS sensitivity, and can be used as a substrate to realize low-concentration detection of common harmful substances such as rhodamine 6G (R6G), crystal violet (CV) and pesticide residue glyphosate in food.

The invention relates to preparation of a sulfydryl-containing covalent organic framework (COF) and application of the sulfydryl-containing covalent organic framework in photocatalytic full water splitting performance. The invention provides a sulfydryl-containing covalent organic framework material (TFDBD-COF), and aims to solve the problems of low photocatalytic full water splitting efficiency and low visible light utilization rate of the existing covalent organic framework material. The method comprises the following steps: 1, preparing a TFPa-COF material; and 2, preparing the TFDBD-COF material. The two-dimensional covalent organic framework material is applied to the field of photocatalytic complete water splitting, experiments show that the material has excellent photocatalytic complete water splitting performance, the complete water splitting hydrogen production rate can reach 158 [mu] mol.h <-1 >. G <-1 > under visible light irradiation, the oxygen production rate can reach 78 [mu] mol.h <-1 >. G <-1 >, a new thought is provided for development of the two-dimensional covalent organic framework, and the two-dimensional covalent organic framework material has important significance.

The invention belongs to the technical field of production of high value-added chemicals and catalysts, and particularly relates to a preparation method of a hollow FeCo2O4-coated CuCo2O4 Z type heterostructure photoelectric catalyst and application of the hollow FeCo2O4-coated CuCo2O4 Z type heterostructure photoelectric catalyst in photoelectric NH3 production. The preparation method comprises the following steps: dispersing ZIF-67 in ethanol, adding K3 [Fe (CN) 6], obtaining a precursor through an ion exchange method, dispersing the precursor in ethanol, adding a Cu (CH3COO) 2 aqueous solution, stirring in a water bath, centrifuging, collecting a product, drying the obtained product, and calcining to obtain a target product. The yield of NH3 catalytically synthesized by the photoelectric catalyst prepared by the preparation method disclosed by the invention within 60 minutes is up to 26.124 mg under the irradiation of visible light and the action of specific additional bias voltage. The prepared photoelectric catalyst has the characteristics of high efficiency, low cost and good nitrate adsorption performance, and can be applied to the field of preparation of NH3 through photoelectric catalysis.

The invention belongs to the technical field of production of high value-added chemicals and catalysts, and particularly relates to a preparation method of an In2S3 (at) PDA / SA / PDMS / MS three-phase integral photocatalyst for producing H2O2. The preparation method comprises the following steps: preparing In-Co PBA nano-cubes through a precipitation reaction of InCl3 and K3 [Co (CN) 6], obtaining In2S3 through a one-step anion exchange reaction, loading polydopamine PDA on the surface of the In2S3 through an in-situ polymerization reaction to synthesize an In2S3 (at) PDA photocatalyst, mixing the In2S3 (at) PDA with sodium alginate SA hydrogel, and loading the mixture onto a PDMS modified melamine sponge MS to obtain the In2S3 (at) PDA / SA / PDMS three-phase (gas-liquid-solid) integral photocatalyst. Under the irradiation of visible light, the yield of H2O2 produced by the monolithic catalyst within 90 minutes reaches 4.6 mmol / g. The method has the characteristics of simplicity, convenience, high efficiency and low cost, and can be applied to photocatalytic production of H2O2.

This invention belongs to the field of photocatalyst materials technology, specifically relating to a three-dimensional graphene aerogel photo-self-propelled Fenton catalyst, its preparation method, and its application. The preparation method includes: mixing a graphene dispersion containing ethylenediamine with a phenolic resin prepolymer containing ferrocene, phenols, and an alkaline catalyst; followed by a one-step hydrothermal reaction, washing, and freeze-drying to obtain the three-dimensional graphene aerogel photo-self-propelled Fenton catalyst. This catalyst can be used to degrade organic pollutants in water under visible light irradiation.

The invention provides a copper and carbon co-modified two-dimensional nitrogen-rich carbon nitride catalyst as well as a preparation method and application thereof, and belongs to the technical field of catalytic materials. The copper and carbon co-modified two-dimensional nitrogen-rich carbon nitride catalyst is prepared by taking copper glycinate as copper and a carbon source at the same time and 3-amino-1, 2, 4-triazole as a g-C3N5 precursor through a one-step thermal polycondensation method, and the modification amounts of Cu and C in the prepared catalyst are controlled by changing the ratio of copper glycinate to 3-amino-1, 2, 4-triazole, so that the catalytic performance is improved; by means of mutual coupling of metal and nonmetal, on one hand, the visible light absorption capacity of the catalyst is effectively expanded, efficient photo-induced electron-hole pair separation and transmission are achieved, and on the other hand, the adsorption capacity on pollutant antibiotic tetracycline is remarkably improved; therefore, compared with pure g-C3N5, single C-modified C-C3N5 and Cu-modified Cu-C3N5 catalysts, the prepared g-C3N5 / Cu-C3N5 composite photocatalyst has better performance of removing tetracycline in water through visible light catalysis.

The application relates to preparation of a fluorine-containing triazine group covalent organic framework material and application of hydrogen peroxide production. Three imine bond connected covalent organic framework materials are prepared to solve the problems of low photocatalytic performance and low solar energy conversion efficiency of existing covalent organic framework materials. The method is as follows: 1,3,5-tris(3-fluoro-4-formylphenyl)benzene and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine are prepared into TFBTAPT-COF by a solvent method. The preparation process is simple and effective, reagent consumption is low, and the yield is high; and the photocatalyst provided by the application can effectively improve the hydrogen peroxide production performance. The application is applied to photocatalytic preparation of hydrogen peroxide, and experiments show that the material TFBTAPT-COF has excellent photocatalytic hydrogen peroxide production performance, and the hydrogen peroxide performance can reach 8750mmol g ‑1 h ‑1 under visible light irradiation.

This invention relates to an In2S3 / In2MnS4 photoelectrocatalyst for the production of H2O2 or HClO and its preparation method, belonging to the field of high-value-added chemicals and catalyst production technology. In2S3 hollow hierarchical microtubes are obtained through a solvothermal method, and Mn is converted into hydrogen through ion exchange. 2+ Partial exchange In 3+ An In2S3 / In2MnS4 photocatalyst was obtained. An In2S3 / In2MnS4 / PVDF / NF photocathode was obtained by loading In2S3 / In2MnS4 onto PVDF-modified nickel foam, and an In2S3 / In2MnS4 / CP photoanode was obtained by drop-coating In2S3 / In2MnS4 onto carbon paper. Under visible light irradiation and a specific additional bias voltage, the yields of H2O2 and HClO produced by the catalytic process reached 2107.8 μmol / L and 28.5 mg / L, respectively, within 90 min. This invention is simple, efficient, and low-cost, and can be applied to the photoelectric production of H2O2 and HClO.

The invention discloses an application of an indium calcium sulfide-coated nickel titanate composite photocatalyst in the reduction of hexavalent chromium. The application is carried out in an aqueous solution system, and the catalyst comprises nickel titanate nanorods and indium calcium sulfide nanosheets formed on the nickel titanate nanorods; and the mass ratio of the indium calcium sulfide nanosheets to the nickel titanate nanorods is (0.5-10): 1. The application of the catalyst of the invention can promote the separation of photogenerated charges of indium calcium sulfide, enhance the effect of photocatalytic reduction of hexavalent chromium, and realize the efficient and low-cost treatment of chromium heavy metal polluted water bodies.

The invention provides a novel In2O3 / g-C3N4 heterojunction material and a preparation method thereof. The In2O3 / g-C3N4 heterojunction material is applied to a CO2 gas sensing material based on visible light excitation at room temperature. The nano material combines the unique electronic property of In2O3 and the excellent visible light absorption characteristic of g-C3N4, and the photogenerated charge separation efficiency is improved through the heterojunction effect, so that the CO2 detection performance is remarkably improved. The sensor is high in sensitivity and low in detection limit, has good stability and reusability, is environment-friendly, conforms to the development trend of environmental protection, and has wide application prospects in the fields of environmental monitoring and the like.

The present invention belongs to the field of photocatalysis technology, discloses a photocatalytic water decomposition method based on carbon nitride heterojunction superaggregation method and copolymerization method, constructs a potential CN-based nanostructure; uses urea and cyanuric acid to establish a superaggregation method, uses 2-amino hypoxanthine to modify the nanostructure, and generates a novel nucleophilic donor-acceptor conjugated polymer; the prepared nucleophilic donor-acceptor conjugated polymer is analyzed under different characterizations, theoretical DFT and electrostatic potential diagrams, and applied to water reduction and water oxidation produced by water splitting under sunlight λ>420nm. The heterojunction prepared by the present invention exhibits significant visible light activity, as well as excellent isolation and distribution performance of electron carriers and holes, which explains its high activity in the process of water splitting into hydrogen (H2) and oxygen (O2). Therefore, the present invention provides a direct and low-cost method to develop and construct a very reliable metal-free photocatalyst.

The invention discloses a titanium dioxide material loaded with graphene and copper nanoparticles, titanium dioxide microspheres assembled by titanium dioxide nanosheets are used as a matrix, the graphene and the copper nanoparticles are loaded on the titanium dioxide microspheres, and a preparation method of the titanium dioxide material comprises the following steps: (1) uniformly dispersing the titanium dioxide microspheres in a solvent alcohol, and uniformly stirring; then adding graphene oxide, uniformly stirring, then adding a copper chloride solution, and uniformly stirring again to obtain a precursor solution; and (2) adding sodium borohydride into the precursor solution for reduction to obtain the titanium dioxide material loaded with the graphene and the copper nanoparticles. According to the titanium dioxide material loaded with the graphene and the copper nanoparticles, the nanosheet assembly structure of the titanium dioxide is reserved, meanwhile, the graphene and the elemental copper nanoparticles are loaded, the visible light absorption performance of the titanium dioxide is improved through loading of the graphene, compounding of photo-induced electrons and holes is inhibited to a certain extent, and the visible light absorption performance of the titanium dioxide is improved. And the effective separation of photon-generated carriers is further realized through the loading of the copper nanoparticles, so that the material shows excellent performance of photocatalytic decomposition of water to produce hydrogen.

The invention discloses a preparation method of an Au nanorod doped Bi4O5I2 nano photocatalyst, and relates to the technical field of photocatalysis, the preparation method comprises the following steps: S1, preparation of Au nanorod seeds; s2, preparation of an Au nanorod; s3, preparing a nitric acid aqueous solution, respectively dissolving Bi (NO3) 3.5 H2O and NaI in the nitric acid aqueous solution according to a specified proportion to form a solution A and a solution B, and then adding NaOH alkali liquor to obtain a white solution; s4, adding the amaranth Au nanorod and sodium dodecyl benzene sulfonate to obtain a mixed solution; and S5, transferring the mixed solution into a Teflon reaction kettle, preparing precipitate powder, putting the precipitate powder into a tubular furnace, and calcining to obtain the Au nanorod doped Bi4O5I2 nano photocatalyst. According to the Au nanorod doped Bi4O5I2 photocatalyst, the visible light absorption rate of the material is enhanced through the surface plasma resonance effect (SPR), and meanwhile, electrons are captured through a Schottky barrier between the Au nanorod and a Bi4O5I2 interface, so that recombination of photon-generated carriers is inhibited, and the photocatalytic activity is further improved.

The invention discloses a preparation method of hollow amorphous N-TiO2 with photocatalytic high-concentration Cr (VI), which comprises the following steps: by taking three-dimensional Fe3O4 as a structural framework and ultrasonically mixing bis (2-hydroxypropionic acid) titanium dihydroxide as a titanium source, hydrolyzing at low temperature to form Fe3O4 / amorphous TiO2; and reacting in an ethylene glycol solution mixed with urea, and treating with a low-concentration acid solution to obtain the hollow amorphous N-TiO2 photocatalyst. Wherein the content of di (2-hydracrylic acid) diammonium titanium dihydroxide is the main reason of the thickness difference of the shell layer, and the low crystallization power is the key for obtaining the generation and stability of the amorphous material. Detection results show that the structure of the prepared hollow amorphous N-TiO2 shows typical amorphous characteristics, such as excellent photocurrent signals, low interface resistance and strong oxygen vacancy signals, so that the photocatalyst can degrade Cr (VI)-containing wastewater with the concentration of 0.274 g / L under the irradiation of visible light.

The invention relates to preparation of a samarium and cobalt co-doped bismuth ferrite nano material and application of the samarium and cobalt co-doped bismuth ferrite nano material in the field of piezoelectric light concerted catalysis. Compared with pure-phase BiFeO3, the samarium and cobalt co-doped bismuth ferrite nano material synthesized by a coprecipitation method shows a remarkably enhanced piezoelectric optical effect. Under the synergistic effect of ultrasound and light, the samarium and cobalt co-doped bismuth ferrite nano material can achieve efficient degradation of rhodamine B and remarkable improvement of hydrogen production efficiency, the degradation rate constant is 14.36 times that of pure-phase BiFeO3, and the hydrogen production efficiency is 1.73 times that of pure-phase bismuth ferrite. By doping the samarium element, the piezoelectric coefficient of bismuth ferrite is improved, and the efficiency of piezoelectric light concerted catalytic reaction is further improved. The cobalt element is doped into the bismuth ferrite, so that the photocatalytic activity of the bismuth ferrite is improved, and the piezoelectric light synergistic catalytic performance of the material is effectively improved. The invention provides a method for improving rhodamine B degradation and water decomposition of the material to generate hydrogen through element doping, and the method has the characteristics of simple process flow and strong operability, and has wide application prospects.

The invention belongs to the technical field of surface enhanced Raman scattering (SERS) substrates, and provides a magnetic ternary composite SERS substrate capable of being degraded and recycled through photocatalysis as well as a preparation method and application of the SERS substrate. The method comprises the following steps: carrying out modification treatment on Co / C or Co / C / g-C3N4 by using (3-aminopropyl) triethoxysilane, so as to obtain modified Co / C or modified Co / C / g-C3N4; mixing the modified Co / C with the Ag NPs solution to obtain Co / C / Ag; co / C / Ag and g-C3N4 are mixed for incubation, Co / C / Ag / g-C3N4 is obtained, or modified Co / C / g-C3N4 and an Ag NPs solution are mixed, and Co / C / g-C3N4 / Ag is obtained. The magnetic ternary composite SERS substrate capable of being degraded and recycled through photocatalysis is designed and prepared, and very excellent enhanced Raman performance and visible light catalysis effect are achieved.

The invention relates to an In2O3 / PPy / g-C3N4 heterojunction material synthesized by a solvothermal method and an in-situ polymerization method. The In2O3 / PPy / g-C3N4 heterojunction material is used for detecting CO2 gas at room temperature and under visible light irradiation. According to the composite material, the unique electronic property of In2O3, the high conductivity of PPy and the good visible light absorption characteristic of g-C3N4 are combined, and the photogenerated charge separation efficiency is improved through the heterojunction effect, so that the CO2 detection performance is remarkably improved. The sensing material not only has high sensitivity and low detection limit, but also has good stability and reusability, is environment-friendly, conforms to the development trend of environmental protection, and has wide application prospects in the fields of environmental monitoring and the like.

The invention provides a bithiazole spacer-containing oligomeric receptor as well as a preparation method and application thereof. The oligomeric receptor is a small molecule receptor which takes bithiazole as a bridging spacer and is externally connected with a benzothiadiazole (BTP) unit or a quinoxaline (Qx) unit or a phenazine (Pz) unit as a central core. The oligomeric acceptor containing the bithiazole spacer has relatively good light capturing capability, proper electron energy level and relatively strong molecular accumulation; and when being applied to organic solar cells as an electron acceptor material, the compound has relatively high photoelectric conversion efficiency.