11 results about "Bismuth oxybromide" patented technology

The invention discloses a full-spectrum response BiOBr / Bi2O3-x / WO3-x double-S heterojunction material rich in oxygen vacancy as well as a preparation method and application of the full-spectrum response BiOBr / Bi2O3-x / WO3-x double-S heterojunction material. The heterojunction is prepared by taking bismuth nitrate pentahydrate, potassium bromide and WO3-x microspheres containing oxygen vacancies as main raw materials through a wet impregnation method, and the value range of x in Bi2O3-x and WO3-x is 0 < = xlt; 1 represents that the two have oxygen vacancies with certain concentration. Due to the introduction of the wide-spectrum response semiconductor materials WO3-x and Bi2O3-x, the double-S-type heterojunction shows a remarkable full-spectrum absorption capability. Meanwhile, oxygen vacancies in the material can serve as effective electron capture centers and transmission channels, and separation of photo-induced electron-hole pairs is effectively promoted. Based on the synergistic coupling effect among BiOBr, Bi2O3-x and WO3-x, the heterojunction can degrade ciprofloxacin (CIP) and reduce Cr (VI) (85% and 74% respectively) at the same time. The heterojunction material provided by the invention is simple in preparation process and good in repeatability, and has important application potential in the field of environmental governance.

The invention belongs to the technical field of air pollution prevention and control of photocatalytic materials, and particularly relates to a nitrogen-doped bismuth oxybromide-graphite phase carbon nitride heterojunction photocatalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: 1) respectively dissolving ammonium sulfate, bismuth nitrate and potassium bromide in water, mixing and transferring into polytetrafluoroethylene, and obtaining nitrogen-doped bismuth oxybromide by utilizing a hydrothermal method; 2) adopting a hydrothermal-assisted thermal polymerization method, obtaining a precursor through a melamine hydrothermal reaction, and performing nitrogen calcination to obtain tubular graphite-phase carbon nitride; 3) adding the mixed sample into methanol, and adopting a mechanical stirring method to obtain the nitrogen-doped bismuth oxybromide-graphite phase carbon nitride heterojunction photocatalyst. Due to the formation of the heterojunction, the activity of the nitrogen-doped bismuth oxybromide-graphite phase carbon nitride in photocatalytic reduction of carbon dioxide can be greatly improved.

This invention relates to the field of nanoscale full-spectrum photocatalytic materials, and particularly to a method for preparing a molybdenum selenide / oxygen-deficient bismuth oxybromine@gold three-phase Z-type heterojunction photocatalyst. This method solves the problems of low photogenerated electron-hole separation efficiency, narrow full-spectrum response range, and poor stability in existing bismuth-based photocatalysts. The preparation method involves first preparing oxygen-deficient BiOBr nanospheres via a solvothermal method, then directly reacting tetrachloroauric acid with oleylamine in toluene to prepare small-particle-size monodisperse Au nanoparticles, which are then combined with oxygen-deficient BiOBr to prepare a BiOBr@Au nanosphere core-shell structure. Finally, a MoSe2 / oxygen-deficient BiOBr@Au three-phase composite material is prepared via a hydrothermal reaction. The catalyst of this invention exhibits absorption capacity under the full spectrum of light, and simultaneously achieves a synergistic enhancement of carrier separation efficiency and strong redox capability, demonstrating excellent photocatalytic activity and the ability to efficiently degrade pollutants and produce hydrogen.

The invention discloses a synthesis method and application of a bismuth-rich bismuth oxybromide solid solution single crystal nanosheet for visible light driven full water decomposition. According to the method, bismuth oxide and lanthanum oxide are used as raw materials, a binary molten salt system of potassium bromide and lithium bromide is used as a bromine source, the bismuth-rich bismuth oxybromide solid solution single crystal is synthesized in situ, in the process, the stoichiometric ratio of the bismuth oxide to the lanthanum oxide is regulated and controlled, complete mutual dissolution of the lanthanum and the bismuth in crystal lattices can be achieved, and the bismuth-rich bismuth oxybromide solid solution single crystal is obtained. Therefore, the formed bismuth-rich bismuth oxybromide solid solution is stable in structure. The prepared bismuth-rich bismuth oxybromide solid solution monocrystal nanosheet has the advantages of simple synthesis process, good repeatability and the like, meets the requirements of large-scale production, not only has an energy band structure required by a full-water decomposition reaction, but also can effectively inhibit the compounding process of photo-induced electron-hole pairs, and is suitable for large-scale production. The separation efficiency and the surface migration rate of current carriers are remarkably improved, so that wide application prospects are shown.

The invention discloses an application of a QL-COF-BiOBr composite material in synchronous reduction of Cr (VI) and degradation of butyl xanthate composite wastewater treatment. The composite material is composed of a QL-COF matrix and bismuth oxybromide nanoparticles loaded on the surface and in pores of the QL-COF matrix and is used for treating composite wastewater containing Cr (VI) and butyl xanthate, and Cr (VI) reduction (the reduction rate is larger than or equal to 90%) and butyl xanthate degradation (the degradation rate is larger than or equal to 95%) are synchronously achieved through the adsorption-photocatalysis synergistic effect. The composite material has high adsorption capacity and high photocatalytic activity, the preparation process is simple, the stability is high, large-scale production is easy, the process is simplified during composite wastewater treatment, the cost is low, and the composite material is suitable for industrial popularization and application.

The present application relates to a kind of bismuth oxybromide / biochar composite for nitrogen fixation and preparation method and its application in photocatalytic nitrogen fixation.The composite is composed of layered porous biochar and rose-like bismuth oxybromide, bismuth oxybromide nanosheet is vertically or obliquely oriented growth in the two-dimensional surface and three-dimensional pore inside of biochar, form 0D-2D face-face contact heterostructure, rather than traditional point-face contact.The preparation method includes controllable preparation of corn straw biomass BC carrier and in-situ growth induced by chemical bond.And its application in photocatalytic nitrogen fixation.By introducing the physical support function of biochar, the problems of BiOBr nanosheet easy to agglomerate, few surface active sites, weak nitrogen adsorption and activation ability, poor cycle stability and short service life are solved.

The invention is applicable to the technical field of preparation of composite fiber materials, and provides a preparation method and application of a multifunctional photocatalytic composite fiber membrane, and the multifunctional photocatalytic composite fiber membrane is prepared by loading composite photocatalytic functional particles on a composite fiber membrane with adjustable aperture through an electrostatic spinning technology by utilizing intermolecular hydrogen bond interaction. The pore-diameter-adjustable composite fiber membrane is formed by using hydrophobic fibers as a supporting framework and hydrophilic fibers as a water transmission material; according to the composite photocatalytic functional particles, bismuth oxybromide grows in situ on the surface of a wide-band-gap semiconductor through solvothermal reaction to construct a heterostructure, and bismuth elementary substances and silver elementary substances are loaded by means of photodeposition to jointly enhance visible light absorption and utilization efficiency. The multifunctional photocatalytic composite fiber membrane prepared by the invention integrates hydrophobic support, hydrophilic transport and photocatalytic functions, and can efficiently remove various pollutants such as heavy metals and metalloids, dyes, antibiotics and phenolic compounds.

The application provides an electrosorption material for electrochemically extracting bromine and a preparation method and application thereof. The electrosorption material comprises bismuth oxybromide nanosheets and polyethylenedioxythiophene loaded on the surface of the bismuth oxybromide nanosheets, and the mass ratio of the bismuth oxybromide nanosheets to the polyethylenedioxythiophene is 1-10:0.1-5. The electrosorption material provided by the application has a large adsorption capacity, good cycle stability and excellent selective adsorption. The electrosorption material still has adsorption capacity for a solution with a bromide ion content of less than 100 mg / L, and is suitable for extracting bromine in oilfield brine.

The invention discloses a Br / O double-vacancy double-bismuth-based crystal form-amorphous junction as well as a synthesis method and application thereof, and belongs to the technical field of catalysts. The synthesis method comprises the following steps: taking manganese-doped bismuth oxybromide as a matrix, and forming Mn < 4 + > in a hydrothermal reaction through doping of manganese ions to promote the formation of bromine vacancies in the bismuth oxybromide, so as to obtain the manganese-doped bismuth oxybromide; amorphous bismuth tungstate partially covers the surface of a substrate of manganese-doped bismuth oxybromide in a non-continuous manner, and oxygen vacancies are formed in the amorphous bismuth tungstate through hydrothermal reaction. The special energy band structure of the catalyst can generate photo-induced electrons required for reducing Cr < 6 + > ions, and bromine vacancies are formed after manganese doping; the amorphous bismuth tungstate not only serves as an electron generation and transfer center, but also forms a heterojunction through an interface coupling effect; the optimization promotes the formation of Br / O double vacancies in the heterojunction, effectively inhibits the recombination of photon-generated carriers, and finally enables the photoreduction rate of the system to 100 mg.L <-1 > Cr < 6 + > ions under visible light to reach 8.5 times of that of a manganese-doped bismuth oxybromide material, thereby realizing the Br / O double-vacancy double-bismuth-based crystal form-amorphous junction, the synthetic method and the photoreduction effect of high-concentration Cr < 6 + > ions.

The application discloses a sulfur-doped lignin-based carbon / bismuth oxybromide photocatalytic material and a preparation method and application thereof, and belongs to the photocatalytic field.The application prepares a flower-shaped sulfur-doped lignin-based carbon / bismuth oxybromide photocatalytic material through a one-pot solvothermal method by taking a sulfur-doped lignin-based carbon dispersion liquid as a reaction solvent.The sulfur-doped lignin-based carbon serves as a structure directing agent to form the flower-shaped photocatalyst, and the lignin serves as a carbon source and the feather serves as a sulfur-doped precursor, so that the advantages of greenness, economy and sustainability are achieved, and the environmental pollution can be alleviated and the recycling of waste resources can be improved.Compared with bismuth oxybromide, the specific surface area of the sulfur-doped lignin-based carbon / bismuth oxybromide is larger, the light absorption is better, and the photo-generated carrier separation efficiency is high.The photocatalytic material is used for photocatalytic reduction of Cr(VI) under visible light, has the advantages of simple preparation method and high visible light catalytic activity, and provides an economic, green and sustainable way for Cr(VI) reduction.

The present application relates to the field of semiconductor materials, and aims to provide a preparation method of a photocatalytic material responding to ultraviolet, visible and near-infrared light simultaneously.The method comprises the following steps: mixing rare earth ion doped bismuth oxybromide, an alcohol solvent and a molybdenum disulfide quantum dot dispersion liquid, continuously stirring and mixing uniformly, and performing a hydrothermal reaction; after the reaction is completed, naturally cooling to room temperature; and after the obtained precipitate is filtered, washed, centrifuged and dried, a molybdenum disulfide quantum dot loaded bismuth oxybromide used as a photocatalytic material is obtained.The present application obtains a certain concentration of oxygen vacancies in the crystal lattice through doping and morphology control means, the oxygen vacancies can effectively promote the separation and migration of photo-generated carriers, and an intermediate energy level is formed in the original energy band structure; while the energy of the ultraviolet and visible light bands in the solar energy is retained, the utilization of near-infrared upconversion light is also expanded.Therefore, the performance of the photocatalyst can be further improved, and the utilization efficiency of light energy in practical application is improved.