1692 results about "Rhodamine B" patented technology

The invention discloses a high-efficiency graphene / silver phosphate composite visible light photocatalyst and a preparation method thereof, belonging to the technical field of composite materials and environmental management photocatalysis. The preparation method comprises the following steps: dissolving graphene oxide in water, and carrying out ultrasonic treatment to obtain a graphene oxide dispersed liquid; dissolving silver nitrate in deionized water, gradually and dropwisely adding into the graphene oxide dispersed liquid while stirring to obtain a mixed solution, uniformly stirring, and aging; dropwisely adding a prepared disodium hydrogen phosphate or sodium dihydrogen phosphate solution into the graphene oxide-silver nitrate mixed solution, continuing stirring, transferring into a hydrothermal reaction kettle, carrying out hydrothermal reaction, and cooling to room temperature; and washing the reaction product, and carrying out vacuum drying to obtain the visible light photocatalyst. The invention has the advantages of wide material sources and simple preparation process; and the obtained composite material has the advantages of controllable structure and regular pattern, and has high-efficiency degradation effect on organic dyes rhodamine B and methylene blue with certain concentration under the visible light irradiation.

The invention relates to a graphene / mesoporous titanium dioxide visible light catalyst and a preparation method, and belongs to the technical fields of nanometer composite materials and photocatalysis. The method comprises the following steps of: adding a graphene oxide into glacial acetic acid, and performing ultrasonic dispersion to obtain dispersion liquid of the graphene oxide; and adding a titanium source into the dispersion liquid of the graphene oxide, and preparing the graphene / mesoporous titanium dioxide nanometer composite visible light catalyst in a one-step in-situ form by a hydrothermal method. The graphene / mesoporous titanium dioxide visible light catalyst has the advantages of readily available raw materials and low cost, the preparation process is simple and convenient, and titanium dioxide in the obtained nanometer composite material has a nanometer poroid structure, a regular size and a special appearance; and titanium dioxide nanometer granules can be distributed onthe surface of graphene and are high in dispersity. Photocatalytic degradation experiments indicate that the graphene / mesoporous titanium dioxide nanometer composite light catalyst has a good photocatalytic degradation effect on rhodamine B under the irradiation of visible light, and is an ideal nanometer composite visible light catalyst.

The invention relates to a silver doped grapheme-zinc oxide nano composite photocatalytic material and a method for preparing the same and belongs to the technical field of nano composite materials and photocatalysis. Graphite oxide is subjected to ultrasonic dispersion to obtain a dispersion solution of graphene oxide; precursors of silver ions and zinc ions are added in the dispersion solution of the graphene oxide, and the mixture is placed into a reaction kettle to be subjected to hydro-thermal treatment to be prepared into the silver doped grapheme-zinc oxide nano composite photocatalytic material in situ after the pH is regulated to an alkaline condition. Photocatalytic degradation experiments show that the silver doped grapheme-zinc oxide nano composite photocatalytic material prepared through the method has good adsorption and visible light photocatalytic degradation effects on rhodamine B and is an ideal nano composite photocatalytic material.

The invention relates to a silver-modified carbon nitride composite photocatalytic material and a preparation method thereof. The preparation method comprises: dissolving dicyanodiamide or melamine in deionized water or dimethyl sulfoxide and performing ultrasonic dispersing, so as to obtain a dicyanodiamide or melamine dispersion liquid; dissolving silver nitrate in deionized water and stirring uniformly, so as to obtain a silver nitrate solution; slowly dropwise adding the silver nitrate solution into the above dicyanodiamide or melamine dispersion liquid under the condition of magnetic stirring, and continuing stirring the solution, so as to obtain a mixed precursor solution; using anhydrous ethanol and deionized water repeatedly wash the obtained mixed precursor solution for multiple times, and performing vacuum drying; and putting the obtained product in a proper crucible and covering, putting in a high-temperature furnace, and sintering for a period under the condition of nitrogen protection, so as to obtain a powdery sample. The advantages comprise that the raw material source is wide, the preparation technology is simple and practicable, and the cost is relatively low; and the prepared composite photocatalytic material has relatively good photocatalytic degradation effect on organic dye rhodamine B under irradiation of visible light.

The invention relates to a fluorescent ion probe (I) with high selectivity and high sensitivity in detection and the application of the fluorescent ion probe in identifying and detecting heavy metal ion and transition metal ion, wherein, the Y is an organic conjugate group with fluorescence transmitting function such as pyrene, naphthalene, 4-amidogen-1, 8-naphthyl imide, Dan sulfonamide, anthracene, carbazole, benzimidazoins, benzoxazoles, boron fluoride bipyrrole (BODIPY), fluorescein, 3, 4, 9, 10-perylenetetracarboxylic diimide or rhodamine B; the X is acylamino group, sulfoamino group or ester group. The fluorescent ion probe uses the fluorescence peak of fluorescence chromophore aggregate as the response signal to identify metal ion, thereby effectively avoiding the quenching effect of transition metal ion and heavy metal ion on fluorophore; moreover, the fluorescent ion probe realizes selective identification of heavy metal ion and transition metal ion in various solvents and aqueous solution in particular.

The invention belongs to the field of nanoscale composite materials, and specifically, relates to a preparation method of a fluorescent mesoporous silica-based core-shell nanoscale capsule. The fluorescent mesoporous silica-based core-shell nanoscale capsule is characterized in that fluorescent mesoporous silica is prepared into shells; and the shells are coated on core materials with different functions, wherein the core materials comprise ferroferric oxide nanoscale particles, gold nanoscale rods and the like. The preparation method of the fluorescent mesoporous silica-based core-shell nanoscale capsule comprises the following steps that cetyl trimethyl ammonium bromide (CTAB) molecule-protected nanoscale particles with different functions are prepared; silica shells are formed on outer layers of the CTAB molecule-protected nanoscale particles with different functions; silane reagent-coupled fluorescent molecule rhodamine B is added into the CTAB molecule-protected nanoscale particles with the silica shells, and undergoes a copolycondensation reaction with tetraethoxysilane to be fixed on the silica shells; CTAB molecules are removed by washing so that a mesoporous silica structure is formed; and polymine is utilized for external modification and then is etched so that the fluorescent mesoporous silica-based core-shell nanoscale capsule is obtained. The preparation method of the fluorescent mesoporous silica-based core-shell nanoscale capsule has the advantages of simple process, convenience of operation, and more nanoscale capsule product functions. The fluorescent mesoporous silica-based core-shell nanoscale capsule prepared by the preparation method has less toxic and side effects and a size-adjustable cavity, and can be utilized as a carrier of a drug for treating cancers.

The invention discloses a preparation method for a sludge carbon based Fenton-like catalyst. The preparation method uses sludge as a raw material to prepare active carbon with high specific surface area through pyrolysis, and loads iron with the active carbon as a carrier to prepare a high-activity catalyst. The preparation method comprises the following steps: drying the sludge, then carrying out grinding and sieving, carrying out activation with a composite activator, after the completion of activation, carrying out high-temperature anaerobic pyrolysis with a certain heating program so as to prepare sludge carbon, then carrying out pickling, washing, drying, grinding and sieving so as to obtain sludge active carbon with high specific surface area, with the sludge active carbon as a carrier, carrying out impregnating in ferrous sulfate for 1 h, carrying out stirring for 24 h, carrying out drying for 12 h, and calcining the dried active carbon so as to prepare a high-activity sludge carbon based catalyst. The invention provides an effective method for sludge recycling; the catalyst prepared by using the method provided by the invention has high specific surface area and a plurality of active sites, so activity is extremely high; and by utilizing the catalyst provided by the invention, azo dye rhodamine B in water can be effectively removed.

The invention discloses a visible-light catalyst for degrading rhodamine B in water. The chemical formula of the visible-light catalyst is shown as [Cu12(1, 2, 4-triazole)8(H2O)2][alpha-SiW12O40].2H2O. The visible-light catalyst is a compound consisting of a metal-organic framework constructed based on a polyoxometallate structure and a three-dimentional framework structure. Four types of Cu ions which are independent on the crystallography exist in the compound; the Cu ions are mutually connected with a ligand 1, 2, 4-triazole to form a two-dimensional bicycle positive ion framework structure with co-existing of a ternary ring and a deca-membered ring; [alpha-SiW12O40]<4-> negative ions are respectively connected to three copper ions on the two-dimensional dual rings through end group oxygen atoms to form the three-dimentional framework structure. The visible-light catalyst has the advantages of simple preparation method and excellent water stability and can be recycled after degrading; the visible light catalyst is used for degrading the rhodamine B in water by using the light catalyst, so that the solar energy can be fully used. The visible-light catalyst is simple in process, low in cost and excellent in catalytic effect.

The invention relates to a copper ion / mercury ion fluorescence molecular probe, and a preparation method and application thereof. The invention mainly aims to solve the problem of single detection ion in the fluorescence molecular probe for detecting copper ions or mercury ions in the prior art, and the problems of low sensitivity, poor selectivity, high sensitivity to pH value, and the like in most fluorescence molecular probes. The preparation method of the fluorescence molecular probe comprises the following steps: (1) dissolving 1 part of rhodamine B in ethanol, adding 2-5 parts of hydrazine hydrate at room temperature, stirring under reflux for 1-2 hours, cooling, and filtering to obtain a precipitate; and (2) adding 1 part of precipitate into 50-500 parts of mixed solvent composed of methanol and dichloromethane in a volume ratio of 3:1, adding 2-6 parts of 40-60wt% formalin, stirring at room temperature in a nitrogen atmosphere for 6-8 hours, evaporating under reduced pressure to remove the solvent, and carrying out silica gel chromatographic separation to obtain the fluorescence molecular probe. The invention has the advantages of high fluorescence quantum yield, low sensitivity to solvent polarity, high chemical / light stability and the like.

The invention relates to a graphene / silver molybdenum oxide compound visible-light catalyst and a preparation method thereof, in particular to a method for preparing the graphene / silver molybdenum oxide-combined visible-light catalyst by water and heat, belonging to the technical field of compound materials and photocatalysis. The preparation method comprises the following steps: taking graphene oxide, silver nitrate and ammonium heptamolybdate as raw materials according to certain proportion, mechanically stirring and mixing the raw materials uniformly in sequence, adjusting the pH value of solution, and then utilizing hydro-thermal reaction to prepare the graphene / silver molybdenum oxide compound visible-light catalyst. The photocatalytic degradation experiment shows that the graphene / silver molybdenum oxide compound visible-light catalyst prepared by the method has a good phtocatalytic degradation effect on rhodamine B due to the irradiation of the visible light and is ideal.

The invention relates to a novel visible light responding photocatalysis material and a preparation method thereof. The effect of the visible light responding photocatalysis material of the BiOBr micro sphere is obviously superior to that of TiO2 (P25, Degussa), wherein BiOBr is square crystalloid; and the diameter of the sphere is about 5mu m. The invention discusses the effects of the additive amounts of glycol and hexadecyl trimethyl ammonium bromide on the physical, chemical and photocatalytic performances of the synthesized catalyst. The preparation process is simple and environment-friendly. The catalyst can almost completely remove the organic dye rhodamine B under visible light.

The invention discloses a probe reagent for concurrent selection and determination of multiple metal ions, and preparation and appliance, and belongs to the field of organic synthesis and analytical chemistry. Tri (2-aminoethyl) amine serves as a parent, wherein rhodamine B is connected to an amino chain, 2-hydroxy-1-naphthaldehyde groups are connected to other two amino chains respectively, and thus a tripod structured rhodamine-hydroxyl naphthalene derivative probe is prepared. In 1,4-dioxane / water (19 / 1, v / v, pH=7) solution, the probe respectively detects Cu2+, Co2+ and Fe3+ by utilizing rate absorption of different wavelengths, and the detection does not interfere with each other; in acetonitrile / water (19 / 1, v / v) solution, fluorescence emission of different wavelengths under different pHs is utilized, the probe respectively detects Zn2+, Al3+, Hg2+ and Cu2+, and the detection does not interfere with each other; under an ultraviolet lamp of 365 nm, Zn2+, Al3+ and Hg2+ are detected to show blue, pink and orange red fluorescence respectively, and through -Zn2+ mixture detection by the probe, Cu2+ shows blue fluorescence vanishing. The probe structure is as follows.

The invention discloses a preparation method of a manganese zinc ferrite / bismuth oxide magnetic photocatalyst, and belongs to the field of inorganic catalytic materials. The preparation method comprises the following steps of firstly, preparing a bismuth oxide precursor, then preparing a precursor of the manganese zinc ferrite / bismuth oxide composite magnetic photocatalyst, and finally, filtering, washing, drying and roasting to obtain the manganese zinc ferrite / bismuth oxide magnetic photocatalyst. According to the method, the preparation technology is simple; the used equipment is few; the preparation cycle is short; the production cost is low. The prepared magnetic composite photocatalyst is high in photocatalytic activity; the degradation rate of a 10mg / L rhodamine B solution for 2.5 hours reaches 99.1% under simulated sunlight, and the recovery rate reaches 89.3%; the manganese zinc ferrite / bismuth oxide composite magnetic photocatalyst which is recycled for three times has the degradation rate of 85% to rhodamine B within 2.5 hours. The manganese zinc ferrite / bismuth oxide magnetic photocatalyst prepared by the invention can be widely applied to the field of photo-catalyzed degradation of organic pollutants.

A composite photocatalyst, preparation and use thereof are disclosed. The composite photocatalyst is composed of metal oxide and quantum dot material. Based on the photocatalyst, the percentage content of the metal oxide is from 80 to 99.99% by mass, and the percentage content of the quantum dot material is form 0.01 to 20% by mass. The metal oxide is zinc oxide or titanium oxide. The quantum dot material is graphene quantum dot or carbon quantum dot. The preparation is that the metal oxide and quantum dot material are stirred, mixed, ultrasonicated and dried in sequence, and the photocatalyst is obtained. Compared with other photocatalysts, the catalyst has higher catalytic efficiency and faster catalytic rate for Rhodamine B and provides more sufficient and more comprehensive utilization of sunlight.

The invention belongs to the technical fields of chemistry and chemical engineering an environmental engineering, and specifically relates to a preparation method of an Ag2S / Ag3PO4 composite photocatalyst. According to the technical key points of the invention, the method comprises the following steps of: putting Ag3PO4 into a Na2S aqueous solution in a certain S / P molar ratio at the room temperature, and stirring; washing and drying an obtained product; and baking at a certain temperature to obtain a product, i.e., the Ag2S / Ag3PO4 composite photocatalyst. In the method, a series of novel Ag2S / Ag3PO4 composite photocatalysts are obtained by doping Ag2S into the surface of Ag3PO4 through an ion exchange method and baking; and as proved by the application of an Ag2S / Ag3PO4 composite photocatalyst to photocatalytic degradation research on rhodamine B, remarkably higher photocatalytic activity than pure Ag3PO4 can be realized for the composite photocatalyst by easily regulating and controlling the S / P molar ratio of an initial raw material and the baking temperature.

The invention relates to a fluorescent DNA-silver nanocluster, and a preparation method and application thereof. The particle size of the fluorescent DNA-silver nanocluster is 2-10nm. A water solution of the fluorescent DNA-silver nanocluster looks light pink by visual inspection, and looks shiny red under irradiation of an ultraviolet lamp with the wavelength of 360nm. The water solution is excited by light with the excitation wavelength of 530nm, the emission wavelength is 570-800nm, and high fluorescence emission strength is acquired at the wavelength of 618nm; rhodamine B is taken as a reference substance, and fluorescence quantum yield is 35.3%. A method for detecting cupric ions and pyrophosphate ions by the fluorescent DNA-silver nanocluster includes (1), drawing a response standard curve of the corresponding ions to acquire a linear regression equation; (2), substituting the detected fluorescence strength into the linear regression equation to obtain the concentration of the cupric ions or the pyrophosphate ions. The fluorescent DNA-silver nanocluster has the advantages of stable performance and environment friendliness, the detection method is rapid and simple, and the detection sensitivity is high.

The invention provides a novel rhodamine fluorescence probe, and belongs to the field of function materials. The novel rhodamine fluorescence probe provided by the invention is characterized in that rhodamine B (RhB) is used as a raw material and is modified by using diamine so as to prepare rhodamine lactam, further the rhodamine lactam reacts with maleic anhydride (MAH) and amantadine so as to obtain the rhodamine fluorescence probe, and the novel rhodamine fluorescence probe contains multiple amido functional groups and carbon-carbon double bonds, wherein the multiple amido functional groups can react with metal ions, and the carbon-carbon double bonds can react with Hg<2+>. After the spiral rhodamine lactam compound is combined with heavy metal particles, the protonation of lactam nitrogen atoms can result in the reduction of the charge density of the nitrogen atoms, thus the cracking of a C-N chemical bond at the spiral center is triggered, so as to generate the fluorescence change and the color change. The obtained rhodamine derivative has relatively good recognition capability on mercury ions and iron ions in a water solution, the detection limit of the obtained rhodamine derivative on the iron ions reaches 8.3ppm, and the detection limit of the obtained rhodamine derivative on the mercury ions reaches 4.7ppm. The prepared rhodamine derivative can serve as the fluorescence probe and is widely applied to the fields such as environmental engineering, detection and the like.

The invention provides a method for preparing a core-shell ferroferric oxide / graphene oxide composite nano-catalyst. The method comprises the following steps of preparing nanometer ferroferric oxide by utilization of a hydrothermal method, preparing graphene oxide by utilization of a modified Hummers method, preparing the core-shell ferroferric oxide / graphene oxide composite nano-catalyst by utilization of an electrostatic self-assembly method. The catalyst prepared according to the method provided by the invention has the advantages that the adsorptive property is excellent, the stability is good, the catalyst can be cyclically utilized, and an excellent adsorption effect can be achieved during the process of degrading simulated dye rhodamine B.

The invention relates to an application of rhodamine B thio-bishydrazide derivative as Hg<2+> fluorescent probe in Hg<2+> detection in water or blood serum, wherein the structural formula of the B thio-bishydrazide derivative is as shown in formula (I); the Hg<2+> detection is realized by utilizing rhodamine B thio-bishydrazide derivative and Hg<2+> to react to generate B-1,3,4-oxadiazole derivative which has a structural formula as shown in formula (I) and is fluorescent. According to the application provided by the invention, the rhodamine B thio-bishydrazide derivative, namely the Hg<2+> fluorescent probe can be selectively reacted with analyte mercury ion, and the sensitivity and strong fluorescence enhancement effect are prominent; non-destructive and fast detection on the mercury ion can be effectively realized, and significant and wide social value and economic benefit are realized.

The invention relates to fluorescent probe detection, in particular to a derivative L of rhodamine B, preparation thereof and use thereof. The derivative L of the rhodamine B has a structural formula (I). The preparation method of the derivative L of the rhodamine B comprises: firstly, reacting the product of the hydrazinolysis of the rhodamine B with glyoxal to obtain an intermediate compound; and secondly, reacting the intermediate compound with benzyldithiocarbazate in a molar ratio of 1:1 in absolute ethanol under a refluxing condition for 4 to 6 hours, cooling, filtering precipitated solid, washing with absolute ethanol and ethyl ether in turn and drying under vacuum to obtain a target compound. The derivative L of rhodamine B can serve as a fluorescent probe. In the invention, the derivative L of rhodamine B is obtained by an effective synthesis means, the copper ion selectivity is high, and the detection of copper ions can be realized on the basis of optimized experimental conditions.

The invention discloses a visible-light-induced photocatalyst Bi4O5Br2 and a preparation method thereof. According to the visible-light-induced photocatalyst Bi4O5Br2 and the preparation method thereof, an improved low-temperature hydrothermal method is adopted, composition of Bi, O and Br in BiOX is controlled by controlling amount of a bismuth source and a bromine source, and a novel layered-cake-shaped visible-light-induced photocatalyst Bi4O5Br2 is prepared successfully. The preparation method is simple in production process, easy to operate, low in synthesis temperature, high in reaction yield, environment-friendly and low in cost and meets the requirement of actual production, the reaction yield is 92%, and raw materials are easy to obtain. The visible-light-induced photocatalyst has good visible-light catalytic activity, can completely degrade various organic pollutants such as rhodamine b, methyl orange and methylene blue in short time under the visible light irradiation, is small in light corrosion and good in reusability, can be applied to industrial production and particularly has a better application value in organic pollutant degradation through solar photocatalysis, and the market potential is large.

The invention relates to rhodamine derivatives and their preparation method and use. The rhodamine derivatives have a general formula I and can be utilized for determination of Fe<3+>. The preparation method of the rhodamine derivatives comprises that an intermediate produced by the reaction of rhodamine B and ethylenediamine is utilized as a raw material and undergoes a condensation reaction with acetylacetone or ethyl acetoacetate in the presence of ceric ammonium nitrate as a catalyst to produce the rhodamine derivatives. Results of an analysis of a mixed-ion interference-resistant iron-ion specific identification capacity of the rhodamine derivatives and an analysis of a living cell condition adaptation capacity of the rhodamine derivatives show that the rhodamine derivatives have strong iron ion specificity, a strong other cation-resistant capacity and a strong living cell condition adaptation capacity, wherein iron ion concentration detection sensitivity is 1*10<-6>; reaction stabilization time is 20 minutes; and a pH value of a Tris-HCl buffer solution is 5.5 or 6.0. The rhodamine derivatives can be utilized as iron ion induction agents for a non-invasive micro-metering system and realizes determination of Fe<3+> concentration, a Fe<3+> flowing speed and a Fe<3+> motion direction.

The invention relates to a synthesis method for a visible photocatalyst by modifying titanium dioxide (TiO2) by using ammonium fluoride (NH4F). The synthesis method comprises three steps of: preparing a mesocellular foam silica (MCF) molecular sieve, preparing an MCF carrying TiO2 catalyst and modifying MCF / TiO2 by using the NH4F. Compared with the prior art, the carrying catalyst MCF / TiO2 is subjected to NH4F hydrophobic modification through a hydrothermal process and a low-temperature vacuum activation method; as a mesoporous material has extremely high absorption capability, the visible photocatalyst has outstanding absorption performance and catalyzing and degrading performance on ultraviolet and visible light of high-concentration organic pollutants during degrading of organic compounds, such as rhodamine B and the like; furthermore, during hydrophobic modification, if isopropyl alcohol is found to be a solvent, the NH4F hydrophobic modification effect of the prepared catalyst isthe optimal and the hydrophobic stability is quite good; moreover, the synthesis method is simple in operation and low in cost, and the raw materials are easily obtainable.

The invention discloses a mercury ion fluorescence sensor shown in a formula (I). The sensor comprises a rhodamine b framework, anion bonding unit urea or thiourea and a signal element fluorescent molecular radical sensed. The invention further discloses a synthetic method of the mercury ion fluorescence sensor. The invention further provides an application of the mercury ion fluorescence sensor show in the formula (I) in mercury ion detection. Compared with the prior art, the raw materials used by the invention are available, the synthetic steps are simple and the post-treatment is convenient, and industrialized production is easy to realize.

The invention discloses a hydro-thermal synthesis method of a visible light photocatalyst mesoporous Bi2WO6. The hydro-thermal synthesis method comprises the following steps of: dissolving bismuth nitrate into a salpeter solution and stirring so as to obtain a solution A; dissolving sodium tungstate in deionized water and stirring so as to obtain a solution B; dropwisely adding the solution B in the solution A under intense agitation, adding a template agent and stirring so as to obtain a mixing solution, transferring the mixing solution to a reaction kettle an inner container of which is made of polytetrafluoroethylene, and carrying out a 180-degree thermostatic reaction for 24h, so as to obtain white precipitate; and washing for 2-3 times respectively by utilizing deionized water and absolute ethyl alcohol, and carrying out natural air-drying on a product so as to obtain a target object. The hydro-thermal synthesis method provided by the invention has the advantages that the process of the synthesis method is simple, the cost is low, the reaction is mild, the morphology of the product is good, the photocatalytic degradation efficiency is high, and the product is easy to recover, a prepared Bi2WO6 photocatalyst is of a three-dimensional flower shape assembled by nanosheets and has a mesoporous level structure, the Bi2WO6 photocatalyst has high catalytic activity on Rhodamine B, different template agents are adopted so as to have different influences on the degradation and morphology of the product, and the comparison phenomenon is obvious.

The invention provides a nano-mesoporous micro-spherical Ln-Bi5O7I photocatalyst and a preparation method thereof. The nano-mesoporous micro-spherical photocatalyst is 15-30 nm in surface mesopore diameter, is 1-5 [mu]m in average particle size and has an orthorhombic crystal form, wherein nBi + Ln : nI = 0.85-1:1, and nLn : nBi = 0.01-0.055:1. The preparation method includes the steps of: dissolving a bismuth salt, an iodine salt and nitrate containing rare earth ions respectively in certain-quantity ethylene glycol, performing ultrasonic oscillation, adding the rare earth ion solution to the bismuth-containing solution, adding the iodine-containing solution, and performing magnetic stirring to form a precursor Ln-BiOI; performing a hydrothermal reaction to the precursor to prepare Ln-BiOI powder; and maintaining the temperature of the Ln-BiOI at 425-525 DEG C to prepare the Ln-Bi5O7I powder. The Ln-Bi5O7I photocatalyst has homogeneous appearance, has large specific surface area, is strong in stability and has excellent photocatalytic performance in degradation of rhodamine B, methyl orange, phenol, bisphenol A and the like. The method combines advantages of both hydrothermal and thermal-decomposition methods.

The invention discloses a layer by layer self-assembly compound nanofiltration membrane based on natural cellulose polyelectrolyte and a preparation method, belonging to the technical field of membrane separation. The preparation method comprises the following steps: firstly, adopting an ultrafiltration membrane as a base membrane for preparing a compound nanofiltration membrane, carrying out chemical modification on the surface of the base membrane to ensure that the surface of the base membrane has a charge property so as to generate static reaction with a polyelectrolyte; and secondly, through alternating depositing anionic and cationic polyelectrolytes, preparing the compound nanofiltration membrane through a layer by layer self-assembly method. According to the preparation method, the adopted cationic polyelectrolyte is a natural cellulose polyelectrolyte; compared with a currently used synthetic polyelectrolyte, the natural cellulose polyelectrolyte is lower in cost, and is an environmental-friendly resource; and the prepared compound nanofiltration membrane containing natural cellulose is good in hydrophilcity and charge performance so that the surface of the membrane is good in pollution resistance; and the compound nanofiltration membrane has a good retaining property for dye molecules such as divalent metal ions such as Ni<2+>, xylenol orange sodium salt, and rhodamine B.

The invention discloses a core-shell TiO2-BiOCl heterojunction photocatalyst with a large specific surface area and a preparation method thereof. The photocatalyst is prepared by taking an ethanol and glycerol system as a solvent and titanium tetrachloride as a titanium source through a hydrothermal one-step method, and has the specific surface area of 202.8 to 223.5m<2> / g, the pore volume of 0.120 to 0.156m<3> / g and the pore size of 1.64 to 1.71nm. Compared with the prior art, the photocatalyst has the advantages that the common chemical reagents are used, cheap and readily available, the method is simple, and the specific surface area of the synthesized photocatalyst is 202.8m<2> / g which is far more than that of similar commercial products; and meanwhile, high-concentration rhodamine B (RhB) can be quickly degraded under visible light in the presence of the photocatalyst, and the photocatalyst has high activity in a high-concentration RhB and p-chlorophenol system.

The invention discloses a black phosphorus / g-C3N4 composite visible light photocatalytic material. The black phosphorus / g-C3N4 composite visible light photocatalytic material is a product of black phosphorus and g-C3N4 by ball-milling compositing, wherein black phosphorus accounts for 0.5%-50% by weight of g-C3N4. Visible light responding semiconductor black phosphorus is subjected to ball-millingcompositing with g-C3N4 for the first time, and photocatalytic efficiency of g-C3N4 is improved effectively by constructing a heterostructure, so that the prepared black phosphorus / g-C3N4 composite visible light photocatalytic material can be used for degrading organic pollutants, is particularly applicable to degradation of organic photosensitizers and photoinitiators such as rhodamine B and hasgreat application prospect in the field of photocatalytic degradation of organic matter; the black phosphorus / g-C3N4 composite visible light photocatalytic material can be prepared with the ball-milling method, a preparation scheme is simple, and cost is low.

Iodine doped bismuthyl carbonate nanosheet and molybdenum disulfide modified carbon nanofiber composites, preparation method and its application in wastewater treatment are disclosed. Bismuth citrate and sodium carbonate as precursors, sodium carbonate as a precipitating agent, dispersed in a mixed solution of water and ethylene glycol, sodium iodide as a iodine source, nano carbon fiber membrane act as the carrier, to synthesis carbon fiber membrane that modified by iodine-doped Bi2O2CO3 nanosheets; then sodium molybdate and thioacetamide as precursors, dispersed in water to react to obtain iodine doped bismuthyl carbonate nanosheet and molybdenum disulfide modified carbon nanofiber composites. The composite material synthesized through a series of steps exhibit excellent photocatalytic activity for the degradation of Rhodamine B and can be recycled for many times. And this invention has the advantages of simple preparation process, easy recovery and multiple use, etc., and has industrial application prospect in water pollution treatment.