42 results about "BISMUTH SUBIODIDE" patented technology

The invention discloses a ferro-nickel oxyhydroxide-modified bismuth vanadate photoelectrode and a preparation method and application thereof. The preparation method comprises the following steps: firstly, depositing bismuth oxyiodide on the surface of conductive glass, then coating the surface with the deposited bismuth oxyiodide with a dimethyl sulfoxide solution of vanadyl acetylacetonate, annealing, performing alkali soaking and rinsing with water to remove excessive vanadium pentoxide, and then drying to obtain a bismuth vanadate photoelectrode, and modifying ferro-nickel oxyhydroxide on the surface of the bismuth vanadate photoelectrode by adopting a cyclic voltammetry method in a three-electrode system, thus obtaining the ferro-nickel oxyhydroxide-modified bismuth vanadate photoelectrode. The invention further discloses applications of the ferro-nickel oxyhydroxide-modified bismuth vanadate photoelectrode in photoelectrocatalytic decomposition water. The prepared photoelectrode is used for producing hydrogen from photoelectrocatalytic decomposition water, can inhibit the compounding of photon-generated carriers, the service life of carriers generated by a BiVO4 photoelectrode can be effectively prolonged, and the oxygen evolution reaction on the surface of the photoelectrode can be promoted, so that the solar optic hydrogen conversion efficiency of a semiconductor photoelectrode can be improved.

The present invention discloses a defect-rich ultra-thin bismuth oxyiodide nano-sheet preparation method, which comprises: uniformly mixing a bismuth nitrate pentahydrate ethylene glycol solution and a potassium iodide ethylene glycol solution according to a volume ratio of 1:1; adding a small amount of an organic aldehyde reagent to make the organic aldehyde reagent concentration in the mixed solution be 0.2-1 g / L; transferring into to a hydrothermal reaction kettle, and carrying out a heat treatment for 12-24 h at a temperature of 150-180 DEG C; and after the hydrothermal reaction kettle is cooled to a room temperature, carrying out alcohol washing on the olive green product of the hydrothermal reaction kettle, carrying out water washing, and drying to obtain the product. According to the present invention, the viscosity of the ethylene glycol is high, the bismuth nitrate pentahydrate and the potassium iodide react in the high viscosity ethylene glycol system, and the grain growth is slow, such that the generation of the ultra-thin bismuth oxyiodide nano-sheets is easily achieved; and the organic aldehyde has the effects of the usual alcohol solvents and further normally has a certain reduction property, such that the [Bi2O2]<2+> unit on the surface is easily reduced through the organic aldehyde after the bismuth oxyiodide nano-sheets are subjected to ultra thinning so as to cause a lot of defects.

The invention discloses a bismuth oxyiodide / zinc oxide composite material and a preparation method thereof, and applications in piezoelectric-photocatalytic removal of organic pollutants. The preparation method comprises: carrying out annealing treatment on an electric-conducting substrate spin-coated with a zinc oxide seed crystal solution, adding the annealed electric-conducting substrate into aprecursor solution, and reacting to obtain a zinc oxide nano-rod array (ZnO NRs); and adding the zinc oxide nano-rod array into a bismuth oxyiodide precursor solution, and reacting to obtain the bismuth oxyiodide / zinc oxide composite material (BiOI / ZnO NAs). According to the invention, the prepared nanometer composite material is put into an aqueous solution containing bisphenol A, organic pollutants in water are removed through the co-action of ultrasonic waves and visible light after light-shielding adsorption is carried out for half an hour, and after piezoelectric-photocatalytic degradation is carried out for 90 min, the bisphenol A in the aqueous solution is almost completely degraded.

The invention relates to a method for producing a bismuth vanadate film through a two-step technology. The method comprises the following steps: depositing a bismuth oxyiodide (BiOI) film on a glass substrate through an electrodeposition technology, carrying out a reaction on the bismuth oxyiodide film and an ammonium metavanadate solution in a reaction kettle by using a hydrothermal technology at 180 DEG C for 24 h, taking out the obtained reaction product, and washing and drying the reaction product to obtain the final film sample. The bismuth oxyiodide film with good uniformity, high visible light response and excellent performances can be obtained through controlling the electrodeposition parameters of bismuth oxyiodide and the hydrothermal time duration. The production method has the characteristics of simple process, easiness in operation, mild reaction conditions, low cost, energy saving and environmental protection.

The invention provides a bismuth oxyiodide photocatalyst and a preparation method and application thereof. The preparation method comprises the following methods: (1) dissolving bismuth salt in ethylene glycol to obtain a solution A, and dissolving iodide salt in methanol to obtain a solution B; (2) uniformly mixing and dispersing the solution A and the solution B, placing the mixture in a closedcontainer to react at 140-180 DEG C for 6-10 hours, and conducting cooling and separating to obtain a solid C; (3) alternately washing the solid C with an organic solvent and water, and conducting drying to prepare a powdery solid C; and (4) irradiating the powdery solid C under ultraviolet light to obtain the bismuth oxyiodide photocatalyst. The preparation method combines hydrothermal synthesisreaction in the closed container and irradiation under ultraviolet light to prepare the bismuth oxyiodide photocatalyst, and has the advantages of simple preparation method, low cost, no addition of any organic solvent, low reaction temperature, low requirement on devices, safety and environmental protection. The bismuth oxyiodide photocatalyst prepared by the method has more oxygen defects and high catalytic efficiency.

The invention provides a bismuth oxyiodide visible-light-induced photocatalyst and a preparation method and application thereof, belonging to the field of catalytic materials. The preparation method of the bismuth oxyiodide visible-light-induced photocatalyst in the invention comprises the following steps: mixing a bismuth source, an iodine source and ethylene glycol, and carrying out a solvothermal reaction to obtain the bismuth oxyiodide (BiOI) visible-light-induced photocatalyst. According to the invention, the powdery bismuth oxyiodide visible-light-induced photocatalyst with high crystallinity and good photocatalytic activity is prepared by controlling a dosage ratio of the bismuth source to the iodine source and the temperature and time of the solvothermal reaction. The results of embodiments in the invention show that the crystallinity of the bismuth oxyiodide visible-light-induced photocatalyst provided by the invention can reach 70.76%, and the degradation rate of the bismuthoxyiodide visible-light-induced photocatalyst to rhodamine B can reach 95% or above.

The invention discloses a chlorine bismuth oxyiodide (010) / graphene heterostructure and a preparation method and application thereof. The problem that existing bismuth oxyiodide (001) is likely to bedissociated, weak in optical absorption property and low in photocatalytic efficiency is solved. Firstly, dispersion liquid of graphene is prepared, then the dispersion liquid of graphene is mixed with a precursor solution of chlorine bismuth oxyiodide (010), and chlorine bismuth oxyiodide (010) / graphene powder with chlorine bismuth oxyiodide and graphene compounded is generated through a hydrothermal method. Effective separation of light-generated electrons and holes of chlorine bismuth oxyiodide (010) is promoted through the conductive capacity of graphene, the recombination probability of the light-generated electrons and the holes is reduced, and therefore the photocatalysis capacity of bismuth oxyiodide (010) is improved.

The invention relates to the field of a photocatalyst, and discloses a preparation method of an ultrathin bismuth oxyiodide photocatalyst and application thereof. An expression of the ultrathin bismuth oxyiodide photocatalyst is BiOI; the ultrathin bismuth oxyiodide photocatalyst is in a powder form and has a thickness of 0.21 to 0.24 nm and a specific surface area of 280 to 310 m<2> / g. The catalyst has a high specific surface area, is ultrathin, and can carry out photocatalytic oxidation better in visible light to remove polyacrylamide in shale gas oil field wastewater; and moreover, according to the preparation method, production cost is reduced, and the production process is simplified.

The invention discloses a preparation method of a flowerlike BiOI-Ti bionic compound catalytic film and application thereof. The preparation method comprises the following steps: first, doping titanium in bismuth oxyiodide (BiOI) in a compound photocatalyst BiOI-Ti; and then loading the compound photocatalyst BiOI-Ti to a bionic compound film PAD@PVDF to obtain the BiOI-Ti / PDA@PVDF biotic compoundcatalytic film. The method of preparing the bionic compound catalytic film is free of harmful intermediate products and is a green and environment-friendly preparation method. The prepared bionic compound catalytic film plays roles of adsorbing, degrading and separating, and can remove antibiotics molecules in an aqueous solution effectively. The bionic compound catalytic film has excellent photocatalytic activity.

The invention belongs to the technical field of photocatalytic degradation. The invention discloses a preparation method of a bismuth vanadate / bismuth oxyiodide / bismuth tungstate double-Z type photocatalytic material. The sunlight response range and the light absorption capacity of the composite material can be regulated and controlled mainly by regulating the addition amounts of bismuth vanadateand bismuth tungstate; the target bismuth vanadate / bismuth oxyiodide / bismuth tungstate double-Z type photocatalytic material is obtained. The bismuth vanadate / bismuth oxyiodide / bismuth tungstate double-Z type photocatalytic material prepared by a hydrothermal method has the advantages that the light absorption capability and the light response capability are effectively enhanced; and the Z-type photocatalytic material effectively improves the mobility of photon-generated carriers, has a good degradation effect on aniline, and can be used for photocatalytic degradation of toxic and harmful pollutants in the environment.

The invention relates to a preparation method of a bismuth oxyiodide heterojunction photocatalytic material for efficient catalytic degradation of perfluorinated compounds. The invention belongs to the technical field of photocatalysis. The preparation method comprises the following specific steps: preparing an ethylene glycol precursor solution of bismuth nitrate pentahydrate and potassium iodide, putting the ethylene glycol precursor solution into a reaction kettle to carry out solvothermal reaction, and carrying out high-temperature calcination treatment on the obtained solid material to obtain the BiOI@Bi5O7I heterojunction photocatalytic material. The photocatalytic material prepared by the preparation method provided by the invention has excellent catalytic performance, and the perfluorinated compound PFOA in the water can be efficiently removed under visible light; when the calcination temperature is 390 DEG C, the prepared BiOI-Bi5O7I heterojunction photocatalyst has the best catalytic performance, the degradation rate within 6 h is 81.3%, and a good material basis and technical support are provided for the application of a photocatalytic reaction in wastewater treatment.

The invention discloses a high-adsorption bismuth oxyiodide visible-light-driven photocatalyst and application thereof. The high-adsorption bismuth oxyiodide visible-light-driven photocatalyst is prepared by the following steps: (1) mixing a bismuth salt with an acid and an alcohol solution to obtain a mixed solution A, and preparing powder povidone iodine into an aqueous solution B; (2) slowly dropwise adding the mixed solution A into the aqueous solution B, continuously and uniformly stirring overnight at room temperature, transferring the mixed solution into a three-neck flask, and carrying out high-temperature reaction under stirring and reflux conditions; and (3) separating, washing and drying the obtained reaction product. According to the invention, the high-adsorption bismuth oxyiodide ultrafine powder has the advantages of large specific surface area, capability of better absorbing visible light and strong adsorbability to pollutants to be degraded; and the in-situ regenerated polyvinyl pyrrolidone coated bismuth oxyiodide can be directly attached to the surfaces of viscose and cotton fibers, other chemical reagents do not need to be added for after-finishing, and the finishing method is simple and efficient.

The invention belongs to the technical field of photocatalytic materials, and particularly relates to an I-doped bismuth-based oxyhalide photocatalyst as well as a preparation method and application thereof. The chemical composition of bismuth-based oxyhalide is Bi2MO4Cl, wherein M is Gd or Sm; and [Bi2MO4]<+> and [Cl]<-> layers are alternately stacked and have a perovskite-like layered crystal configuration. The photocatalyst is prepared by adopting a molten salt method, bismuth oxide Bi2O3, M2O3 and bismuth oxyiodide BiOI are mixed and ground uniformly, a salt reaction medium is added for continuous grinding, and then high-temperature calcination, washing and drying are performed to obtain the photocatalyst. The material is applied to a photocatalytic water splitting system for the first time, high oxygen production activity under visible light and hydrogen production activity under a full spectrum are achieved, and good photochemical stability is shown.

The invention discloses a method for preparing a molybdenum-doped bismuth vanadate photoelectrode modified by cobalt phosphide. First, a bismuth iodide oxide photoelectrode is prepared on the surface of a conductive glass by a deposition method, and a vanadium source and molybdenum are added dropwise on the bismuth iodide oxide photoelectrode. source solution, after annealing and cleaning, the molybdenum-doped bismuth vanadate photoelectrode was obtained, and then in the three-electrode system, cobalt phosphide was deposited on the surface of the molybdenum-doped bismuth vanadate photoelectrode through photo-assisted electrodeposition, and the new bismuth vanadate photoelectrode was obtained. The invention also discloses the application of the composite bismuth molybdovanadate photoelectrode in photoelectric catalytic water decomposition. The photoelectrode prepared by the present invention is used for photoelectrocatalytic water splitting to produce hydrogen. Doping molybdenum can effectively increase the concentration of carriers and increase the photocurrent, while electrodeposition of cobalt and phosphorus can effectively delay the recombination loss in the photoelectrode and increase the The lifetime of the photogenerated carriers can promote the oxygen evolution reaction on the surface of the photoelectrode, thereby improving the solar-to-hydrogen conversion efficiency of the semiconductor photoelectrode.

The invention discloses a Z-type photocatalyst as well as a preparation method and application thereof. The Z-type photocatalyst is shown as BiOYnI1-n / Ag / AgI-x, wherein Y is halogen; x is the molar ratio of silver to iodine, and the value of x ranges from 0 to 1; n is 0 to 1; n is not equal to 1. The Z-type photocatalyst is prepared by doping silver and silver iodide into bismuth iodide, thereby improving the defects of weaker catalytic action and lower catalytic efficiency caused by higher conduction band energy level of the bismuth iodide, and remarkably improving the catalytic activity andcatalytic efficiency of the Z-type photocatalyst. Moreover, the preparation method of the Z-type photocatalyst is simple, and the photocatalytic performance of the photocatalyst can be adjusted by controlling the using amount of soluble silver salt and illumination conditions and controlling the content of silver and silver iodide.

The invention discloses a bismuth oxyiodide composite photocatalytic material modified with carbon-coated ferroferric oxide magnetic microspheres as well as a preparation method and an application ofthe bismuth oxyiodide composite photocatalytic material. The preparation method of the composite photocatalytic material comprises the steps as follows: firstly, the carbon-coated ferroferric oxide magnetic microspheres are prepared with a hydrothermal carbonization method and the supported on the surface of bismuth oxyiodide in a hydrothermal co-deposition manner. Pichia pastoris in the compositeis cheap, easy to obtain, non-toxic and harmless, the preparation process is convenient, green and environmentally friendly, the reaction condition is easy to control, and secondary pollution is notproduced. The prepared composite catalytic material has uniform particle size, high light absorption strength, wide absorption range, high photon-generated carrier generation rate, good conduction effect and low composition rate, and the composite photocatalytic material has high stability and certain magnetism, can be recycled under the external magnetic field condition and has environmental protection benefits. The composite photocatalytic material has the advantages of being fast to degrade, high in removal rate, convenient to operate, low in cost, free of secondary pollution and the like when applied to photocatalytic degradation of antibiotic wastewater.

The invention discloses a preparation method of a porous bismuth vanadate film photo-anode, which comprises the following steps: spin-coating a conductive glass substrate with a low-concentration bismuth oxyiodide precursor solution, and treating at low temperature to obtain a bismuth oxyiodide seed crystal layer; spin-coating the seed crystal layer with a high-concentration bismuth oxyiodide precursor solution, and carrying out low-temperature treatment to obtain a thickness-controllable bismuth oxyiodide nanosheet film; and dropwise coating the bismuth oxyiodide nanosheet with a dimethyl sulfoxide solution of vanadyl acetylacetonate, and carrying out calcination and sodium hydroxide aqueous solution treatment to obtain the porous bismuth vanadate film photo-anode. According to the preparation method, the bismuth oxyiodide nanosheet film is prepared mainly through a low-temperature wet chemical method, then the porous bismuth vanadate film is obtained through calcination, the whole preparation process is novel in method and mild in condition, and the prepared bismuth oxyiodide nanosheet film is uniform and compact.

The invention provides a graphene-based photocatalytic material. The graphene-based photocatalytic material is prepared by the following steps: preparing a bismuth-graphene complex from bismuth chloride and liquid polyacrylonitrile as raw materials; mixing and reacting the bismuth-graphene complex with bismuth oxyiodide and chloroplatinic acid to obtain a prefabricated body; and finally, preparinga suspension from the prefabricated body, dropwise adding an alpha naphthylamine monomer, and carrying out polymerization reaction to obtain the graphene-based self-cleaning photocatalytic material.Herein, before the suspension is prepared, the prefabricated body is subjected to heat treatment by using mixed gas of oxygen and nitrogen, so that metal nitrogen oxide is formed on the surface of theprefabricated body. According to the invention, the photocatalytic material has a very good photocatalytic degradation effect on pollutants in air and an aqueous solution.

The invention belongs to the technical field of photocatalytic materials, in particular to an I-doped bismuth-based oxyhalide photocatalyst and its preparation method and application. The chemical composition of the bismuth-based oxyhalide is Bi 2 MO 4 Cl, wherein M=Gd, Sm; [Bi 2 MO 4 ] + and [Cl] − The layers are stacked alternately, with a perovskite-like layered crystal configuration. The photocatalyst is prepared by molten salt method, bismuth oxide Bi 2 o 3 , M 2 o 3 It is mixed and ground evenly with bismuth oxyiodide BiOI, added into a salt reaction medium to continue grinding, and then calcined at high temperature, washed and dried to obtain the photocatalyst. And for the first time, this kind of material was applied to the photocatalytic water splitting system, which achieved high oxygen production activity under visible light and hydrogen production activity under full spectrum, and showed good photochemical stability.

The invention relates to a binary composite semiconductor photocatalyst material Ag 2 CrO 4 / BiOI and its preparation and application, Ag 2 CrO 4 The mass ratio to BiOI is 2‑30:100; BiOI is a bismuth oxyiodide microsphere formed by self-assembly of two-dimensional (2D) nanosheets, and the Ag 2 CrO 4 Deposited on the surface of BiOI nanosheets and in the gaps between the sheets. The preparation method is as follows: (1) under the condition of 26-28°C, uniformly disperse the BiOI and silver source prepared by the solvothermal method in deionized water; add the aqueous solution containing chromate under vigorous stirring, and continue stirring for 30-150min; ( 2) The solid product is obtained by filtration, and the product is fully washed and dried in vacuum at 50-90° C. for 8-24 hours. The molar ratio of silver source and chromate is 2:1. As a photocatalyst for the degradation of organic dyes. Ag of the present invention 2 CrO 4 / BiOI was shown to interact with Ag in the visible light degradation of Rhodamine B 2 CrO 4 similar high activity, while its catalytic stability is higher than that of Ag 2 CrO 4 It has been significantly improved and can be used repeatedly. Moreover, the synthesis route of the preparation method of the present invention is convenient, simple and efficient, and environmentally friendly.

The invention discloses a method for preparing a tin disulfide / bismuth oxyiodide composite photocatalyst with a hydrothermal method. The method comprises the following steps: weighing bismuth nitratepentahydrate and dissolving bismuth nitrate pentahydrate into deionized water; then weighing potassium iodide according to the element molar ratio of Bi to I being equal to 1 to 1, adding a mixed solution, and adjusting the pH value of the mixed solution to 6 to 8; transferring the mixed solution into a homogeneous hydrothermal reactor, and putting the homogeneous hydrothermal reactor into a homogeneous reactor for reaction; after the reaction is ended, carrying out centrifugal washing and drying with the deionized water and absolute ethyl alcohol respectively, thus obtaining bismuth oxyiodidepowder; weighing tin chloride pentahydrate and dissolving tin chloride pentahydrate into the deionized water; after uniform stirring, adding sodium sulfide into the solution, uniformly mixing again,adding the bismuth oxyiodide powder obtained in the former step into the mixed solution and carrying out ultrasonic dispersion to obtain a precursor; transferring the precursor into the homogeneous hydrothermal reactor and the putting the homogeneous hydrothermal reactor into the homogeneous reactor for reaction; after the reaction is ended, taking out a product and then carrying out centrifugal washing and drying with the deionized water and absolute ethyl alcohol respectively on the product, thus obtaining the tin disulfide / bismuth oxyiodide composite photocatalyst.

The invention discloses a photocatalytic antibacterial hydrogel dressing and a preparation method thereof, and belongs to the technical field of medical materials. Dissolving bismuth nitrate in deionized water, and adding potassium iodide under a stirring condition to obtain hydrosol of bismuth oxyiodide; dispersing nano-zinc oxide in deionized water, then adding the hydrosol of bismuth oxyiodide, reacting under a stirring condition to obtain a solid-phase product, washing, and drying in vacuum to obtain a bismuth oxyiodide doped nano-zinc oxide composite material; ultrasonically dispersing the bismuth oxyiodide doped nano-zinc oxide composite material in a polymer adhesive, then adding a humectant, and stirring to obtain the photocatalytic antibacterial hydrogel dressing. The antibacterial property of the bismuth oxyiodide doped nano-zinc oxide composite material prepared by the invention is obviously higher than that of undoped nano-zinc oxide. The photocatalytic antibacterial hydrogel dressing prepared by the method disclosed by the invention not only has a good wetting effect and biocompatibility, but also has a good antibacterial property under visible light.

The invention discloses a graphene / bismuth oxyiodide / graphene sandwich structure photocatalyst, and a preparation method and application thereof. The method combines a dispensing method and a dipping method to establish a new method for graphene / bismuth oxyiodide / graphene composite film and has the advantages of simple preparation method, low price and convenient recycling. According to the catalyst prepared by the method of the invention, the upper and lower surfaces of the bismuth oxyiodide are uniformly combined with the graphene, the photoresponse range is increased, and the catalytic efficiency is greatly improved.

The invention provides a bismuth oxyiodide / boron carbide catalyst and a preparation method and application thereof, belonging to the field of catalytic materials. The catalyst provided by the present invention includes a composite structure of bismuth oxyiodide and boron carbide, and the ratio of the amount of substances of bismuth oxyiodide and boron carbide is controlled to be 1: (0.855~85.5), so that the two are combined to form more semiconductor heterogeneous compounds. Mass junction, electronic transition occurs when responding to visible light, through the connection of the heterojunction, the photogenerated electrons are transferred to the BiOI side, and the hole pairs are transferred to the B 4 On the C side, photogenerated electrons and hole pairs are separated, reducing the recombination rate of the two, thereby increasing the number of active groups in the catalytic reaction system to improve catalytic activity and the degradation rate of endocrine disruptors. After the catalyst provided by the invention is combined with the sulfate oxidation technology, the degradation rate of endocrine disruptor BPS in water can reach 95%, and the degradation rate of BPA can reach 98%.

The invention discloses a method for preparing bismuth oxychloride / bismuth iodide oxide composite ultra-thin nanosheets by ion exchange method. Bismuth nitrate pentahydrate and polyvinylpyrrolidone are dissolved in an ethylene glycol solution, stirred at room temperature until completely dissolved, and saturated. Add sodium chloride solution to the above solution, continue stirring to obtain a white turbid solution, transfer to a hydrothermal reaction kettle to react at 140-180 ° C, and then vacuum-dry at 60 ° C to obtain the product bismuth oxychloride ultrathin nanosheets. The bismuth oxide ultrathin nanosheets were dispersed in a saturated potassium iodide solution, and stirred at 25-50 ° C for 3-12 hours to obtain the target product bismuth oxychloride / bismuth iodide oxide ultrathin nanosheets. The invention has simple and easy operation and good repeatability. The synthesized bismuth oxychloride / bismuth iodide oxide composite ultrathin nanosheet has an ultrathin two-dimensional structure, a large specific surface area, and a bismuth oxychloride / bismuth iodide oxide composite ultrathin nanosheet strip. The gap is suitable, and the light response range is wide, so it has a good application prospect in the related fields such as optics, electricity and heat.

The invention relates to the technical field of wastewater treatment, and especially relates to application of a flower-shaped bismuth oxyiodide material, and a treatment method of organic pollutants in water. The invention provides the application of a flower-like bismuth oxyiodide material as a catalyst for oxidative degradation of organic pollutants in water. The flower-like bismuth oxyiodide material is used as a catalyst to construct a novel oxidation system, and the method has the advantages that the removal efficiency of organic pollutants is high, no toxic byproduct is generated, the material can be recycled, the removal rate is not interfered by inorganic zwitterions, humic acid and other substances, the applicable pH range is wide, and the like. Experimental results show that the flower-like bismuth oxyiodide material is adopted as a catalyst, peracetic acid is adopted as an oxidizing agent, a novel oxidation system is constructed, and various organic pollutants such as phenolic substances and / or sulfonamides in the water body can be effectively degraded, so that the water body is purified.

The invention discloses a ferric tetroxide / bismuth oxyiodide / silver bromide magnetic composite visible light catalyst and a method for preparing the same. Its main features are: ferric tetraoxide / bismuth iodide oxide / silver bromide are heated through hydrothermal treatment. Method synthesis. First, the magnetic ferric oxide and the visible light catalyst bismuth oxyiodide are combined to make the catalyst magnetically recoverable, improving its recyclability; secondly, the ferric oxide / bismuth iodide oxide and silver bromide are combined to form a heterogeneous The structure promotes the effective separation of photogenerated electron-hole pairs and improves the photocatalytic activity. The main preparation steps are: (1) Preparing magnetic ferric oxide by hydrothermal method. (2) Preparation of ferric tetroxide / bismuth iodide magnetic composite photocatalyst by hydrothermal method. (3) Preparation of ferric tetroxide / bismuth oxyiodide / silver bromide magnetic composite visible light catalyst by hydrothermal method. This method has the excellent characteristics of being simple, easy to implement, green and environmentally friendly. The prepared catalyst has high catalytic activity and can be magnetically recycled, so it has good application prospects.

The invention provides a memristor based on bismuth oxyiodide film, its preparation method and application. The memristor in the present invention includes a bottom electrode, on which a resistive switch function layer made of bismuth oxyiodide thin film is formed, and a top electrode is formed on the resistive switch function layer. The present invention uses a bismuth oxyiodide thin film as the resistive switching functional layer of the memristor. Bismuth oxyiodide can increase the number of oxygen vacancies in the device, and these oxygen vacancies can be used as a stable conductive channel between the top electrode and the bottom electrode, thereby making the device There will be no abrupt changes in the resistance of the resistance. Because the memristor in the present invention adopts bismuth oxyiodide film as the resistive function layer of the device, it realizes the simulation of the biological synapse function of the device, including short-term plasticity, long-term plasticity, double-pulse facilitation, and peak-time plasticity , learning-forgetting-relearning, etc., which means that the powerful computing power of the human brain and high-efficiency artificial intelligence chips have an optimistic development prospect.

The invention discloses a bismuth oxyiodide-based composite photocatalyst and a preparation method thereof, and relates to a composite photocatalyst, in particular to a bismuth oxyiodide and cobalt titanate composite photocatalyst. The bismuth oxyiodide and titanic acid composite photocatalyst is of a solid structure; the bismuth oxyiodide and cobalt titanate composite photocatalyst can degrade rhodamine B dye under the irradiation of a catalytic light source; the two-dimensional bismuth oxyiodide nanosheet is loaded on the surface of the one-dimensional porous cobalt titanate nanorod, so thatthe prepared composite photocatalyst has a dendritic hierarchical structure, and photon capture and photon-generated carrier separation are facilitated; the preparation method of the composite photocatalyst is simple, the process parameters are easy to realize, the composite photocatalyst with high yield and ultra-purity can be obtained while the cost is reduced, and the preparation method is suitable for large-scale production; and the method has wide application prospect and industrial prospect in the fields of hydrogen production by photolysis of water, photodegradation of organic pollutants and heavy metal ions, reduction of carbon dioxide and the like.

The invention discloses a method for controllably synthesizing Bi nanosheets with preferred orientations of different crystal planes, belonging to the technical field of micro / nano material preparation. In the present invention, bismuth iodide oxide with different preferred orientations of crystal planes is controllably synthesized under normal temperature and pressure, and then converted into Bi nanosheets with preferred orientations of (012) and (003) crystal planes through electrochemical reduction topologically using this as a template. Bi nanosheets with preferred orientation of (003) facets electrocatalyze CO at ‑0.85V vs. RHE potential 2 The faradaic efficiency of reducing formic acid is as high as 98%, and the partial current density of formic acid production can be greater than 100mA / cm at ‑1.05vs.RHE potential 2 , and has a micron-scale lateral size, a larger surface-to-volume ratio, which can expose more catalytic active sites, which is conducive to electron conduction, and electrocatalyzes CO 2 The reduction of formic acid has higher efficiency and selectivity, is very economical and practical, and has good industrial application potential.