84 results about "Reduction Activity" patented technology

The invention discloses a preparation method of a photocatalytic ferroelectric heterojunction with a photothermal-pyroelectric effect, which comprises the following steps: step 1, preparing carboxylated BaTiO3 nanoparticles (BaTiO3NPs), adding a carboxylic acid modified ferroelectric material and a metal salt solution into a mixed solution of H2O and ethanol, and stirring to obtain a mixed solution; wherein the ferroelectric material is BaTiO3NPs, and the metal salt is In (NO3) 3.4 H2O; 2, adding a mixed solution of ammonia water and an ethanol solution into the mixed solution, reacting in an oil bath at 80 DEG C for 30 minutes, carrying out centrifugal washing and drying to obtain BaTiO3 / In (OH) 3, and carrying out high-temperature calcination in a muffle furnace to obtain a BaTiO3 / In2O3 heterojunction; and step 3, grinding the obtained BaTiO3 / In2O3 and NaBH4 according to a ratio, uniformly mixing the obtained BaTiO3 / In2O3 and NaBH4, and roasting the obtained mixture in a tubular furnace in an argon atmosphere to obtain the black BaTiO3 / B-In2O3 heterojunction. A semiconductor material with photo-thermal conversion performance is combined with a pyroelectric material, so that the prepared heterojunction has relatively high photocatalytic reduction activity, and the catalytic efficiency is improved.

The application discloses a platinum-based high-entropy intermetallic compound and a preparation method and application thereof as a hydrogen fuel cell cathode catalyst, and belongs to the field of fuel cells.The preparation method comprises the following steps: S01, adding platinum salt, at least five other metal salts and a nitrogen-rich organic compound into an organic solvent, uniformly mixing, and obtaining a metal precursor mixed solution; S02, adding a carbon carrier into the metal precursor mixed solution, fully mixing, drying, collecting, and obtaining a precursor; and S03, heat treating the dried precursor under a reducing atmosphere, and performing heat preservation treatment, so as to obtain the platinum-based high-entropy intermetallic compound.The preparation method is simple, low in cost and good in repeatability, the prepared catalyst has the advantages of uniform particle size and high oxygen reduction activity, and has a good development prospect in the field of hydrogen fuel cell catalyst applications.

The invention discloses a covalent organic framework with oxidation-reduction activity and a bionic nano-channel structure as well as a preparation method and application of the covalent organic framework, and belongs to the technical field of environmental protection. According to the preparation method, 2, 4-dihydroxybenzene-1, 3, 5-tricarboxaldehyde and 2, 5-bis (allyloxy) terephthaloyl hydrazine are taken as raw materials, a two-dimensional covalent organic framework with oxidation-reduction activity is synthesized, and then a sulfonic acid group with negative charges is covalently grafted, so that a functional material with a bionic nano-channel structure is formed. The material has regular porous channels and rich functional sites, the porous channels provide efficient mass transfer paths and adsorption spaces for uranyl ions, and the functional sites realize specific recognition of the uranyl ions through oxidation-reduction reaction and electrostatic interaction, so that the material shows synergistic advantages of strong selectivity, high adsorption capacity and rapid adsorption kinetics on uranium. The method is simple and low in cost, and the prepared material is clear in structure, good in hydrophilicity, capable of efficiently adsorbing uranyl ions and good in application prospect.

The invention discloses a nickel-tin alloy-oxide composite material Ni3Sn2-NiSnOx, a preparation method thereof and application of the nickel-tin alloy-oxide composite material Ni3Sn2-NiSnOx in electrocatalytic ammonia synthesis reaction, and belongs to the technical field of electrochemical catalysis. The preparation method comprises the following steps: adding SnCl2. 2H2O and NiCl into deionized water as raw materials, adding glycine, potassium pyrophosphate and urea as electro-deposition auxiliary agents, and stirring for 10 minutes to obtain electro-deposition liquid; and carrying out electro-deposition on a conductive substrate serving as a cathode, so that Ni and Sn are co-deposited to form a nickel-tin alloy, and part of the nickel-tin alloy reacts with oxygen in the deposition process or after deposition to form a nickel-tin oxide phase, so that the Ni3Sn2-NiSnOx composite catalytic material is obtained. By regulating and controlling the concentration of tin ions in the electroplating solution and the electrodeposition time, the component proportion of nickel and tin in the product and the morphology structure of the material can be regulated. The composite material provided by the invention has excellent electrocatalytic nitrogen reduction synthesis ammonia activity and selectivity, and solves the problems that the service life of a catalyst is shortened and the catalytic activity and stability are reduced due to irreversible reconstruction of an alloy compound under high potential.

The invention relates to an hcp phase ordered structure PtCu oxygen reduction catalyst and a preparation method thereof.The preparation method comprises the steps that carbon black and a Cu metal precursor are mixed, and a Cu / C precursor is obtained under the action of a reducing agent; pt and Cu / C are compounded through an impregnation method; the PtCu alloy loaded on the conductive carbon black is ordered through high-temperature gas reduction, and the loaded PtCu intermetallic compound catalyst is obtained. The catalyst nanoparticles prepared by the invention are uniformly distributed on the carbon carrier, the size of the nanoparticles is about 3-5nm, and the alloy structure is an intermetallic compound structure. The preparation process is simple, environment-friendly and suitable for large-scale batch production; the prepared catalyst has high oxygen reduction activity and stability, and can be directly applied to fuel cells.

The invention provides a fluorine-doped Fe-N-C composite material as well as a preparation method, application and regeneration thereof, and belongs to the technical field of water pollution. The preparation method comprises the following steps: firstly, mixing an iron precursor, zinc salt, an organic ligand and an organic solvent to synthesize a Fe-doped metal organic framework Fe (at) ZIF-8 material, and then carbonizing the Fe-doped metal organic framework Fe (at) ZIF-8 material into a Fe-N-C material; and then Fe-N-C and a fluorine source are mixed and subjected to secondary carbonization, and the fluorine-doped Fe-N-C composite material is obtained. Fluorine atoms are introduced into the Fe-N-C material and generate axial coordination with Fe in the center of FeN4, the fluorine element with high electronegativity can effectively improve the isoelectric point of the Fe-N-C material, the reaction activity of the material is enhanced, Fe leaching of the material in the reaction process is inhibited, and the stability of the material is improved. In addition, the prepared fluorine-doped Fe-N-C composite material can continue to be recycled through fluorine doping regeneration, and high reduction activity and stability are kept.

The invention discloses a preparation method of a zero-valent iron reduction material with micro-nano size and water stability, and belongs to the field of underground water pollutant degradation materials. The method comprises the following steps: 1) uniformly mixing micron-sized zero-valent iron powder and hexadecyl trimethoxy silane, and carrying out mechanical ball milling; and 2) cleaning the material with a cleaning agent, and drying to obtain the zero-valent iron reduction material with micro-nano size and water stability. According to the preparation method, a mechanical ball milling method and a hexadecyl trimethoxy silane surface modification method are utilized to cooperate, so that micro-nano size and surface hydrophobicity of the zero-valent iron are stabilized, agglomeration and passivation of the zero-valent iron in water are inhibited, and the reduction activity and water stability of the zero-valent iron material are improved; the reducing capacity of the material on pollutants such as halogenated hydrocarbon and heavy metal in water is remarkably improved, the material can be kept stable in water for a long time, the technical problems that the micro-nano zero-valent iron reducing material is prone to inactivation and difficult to store are solved, and waste of material resources can be reduced.

The invention belongs to the technical field of environmental catalytic purification, and discloses a cobalt-titanium composite oxide catalyst and a preparation method and application thereof. The preparation method comprises the following steps: firstly, preparing a precursor solution from tetrabutyl titanate and cobalt nitrate; then, the precursor solution is subjected to sol and gel treatment and then roasted in an air atmosphere or an inert atmosphere, and a cobalt-titanium composite oxide is obtained; and finally, carrying out heating activation treatment on the cobalt-titanium composite oxide in a hydrogen-nitrogen mixed atmosphere, and then carrying out plasma treatment in an argon-nitrogen mixed atmosphere to obtain the cobalt-titanium composite oxide catalyst. The cobalt-titanium composite oxide catalyst has unique oxidation-reduction activity and stability, can efficiently and continuously catalyze and decompose phenols, cyanides and thiocyanides in wastewater under the conditions of low temperature, normal pressure and wide pH range, is easy to regenerate and can be repeatedly used, and has remarkable advantages compared with a traditional catalyst.

The invention provides a carbon layer coated NiFe nanoparticle difunctional composite electrocatalyst as well as a preparation method and application thereof, and belongs to the technical field of new energy materials. A transition metal organic framework compound with specific morphology and size is synthesized from dimethyl imidazole and transition metal salt, then a nitrogen-doped carbon material (Fe-N-C) with specific morphology and high oxygen reduction activity (ORR) and containing transition metal iron is prepared through pyrolysis, the Fe-N-C material is physically mixed with a nickel precursor and an iron precursor, and the nitrogen-doped carbon material is prepared. And the composite difunctional electrocatalyst with high ORR and oxygen evolution reaction (OER) performance of the NiFe nanoparticles coated with the carbon layer is obtained under a microwave heating condition, and can be applied to a metal-air battery as a cathode catalyst.

The invention belongs to the field of environmental biotechnology and nano material application, and relates to a method for accelerating microorganisms to reduce selenite based on immobilized riboflavin. Aiming at the problems of poor stability, difficulty in recovery, non-repeated use and the like of dissolved riboflavin serving as an electron shuttle, riboflavin is grafted on the surface of a multi-walled carbon nanotube through a covalent binding method, and immobilized riboflavin capable of being recycled is constructed. The material can accelerate extracellular electron transfer of shewanella MR-1, and toxic sodium selenite is efficiently reduced into low-toxicity or non-toxic elemental selenium. Results show that the immobilized riboflavin not only maintains high reduction activity of riboflavin, but also has excellent cyclic utilization performance, still maintains high reduction rate after being repeated for multiple times, and effectively reduces operation cost and resource loss. According to the invention, an efficient, economical and sustainable application scene is provided for a microorganism-electron shuttle combined remediation technology, and a new thought is also provided for application of a functional nano material in an environmental biotechnology.

The invention discloses screening of novel multifunctional selenite reductase SDR-SerA, and belongs to the field of environmental pollutants. A novel multifunctional enzyme capable of reducing selenite is screened from a gene bank in a selenium-rich region, and the reduction activity of the enzyme to S-1-phenylethanol is further represented. According to the invention, selenite reductase is mutated, and site-specific mutagenesis and molecular dynamics (MD) simulation reveal that the mutant M206 affects a lid opening and closing mechanism of an enzyme active site. The novel selenite reductase is reported from a short-chain dehydrogenase / reductase (SDR) superfamily, and a novel method is provided for finding the novel selenite reductase from a wide enzyme library of the novel selenite reductase. The research not only deepens the understanding of the selenium metabolism process, but also lays a foundation for developing an efficient selenium pollution bioremediation technology.

The application provides a fluorine-doped Fe-N-C composite material and a preparation method and application and regeneration thereof, and belongs to the technical field of water pollution. In the application, an iron precursor, a zinc salt, an organic ligand and an organic solvent are mixed to synthesize Fe-doped metal organic framework Fe@ZIF-8 material, and then the Fe@ZIF-8 material is carbonized into Fe-N-C material; then the Fe-N-C material is mixed with a fluorine source and subjected to secondary carbonization to obtain the fluorine-doped Fe-N-C composite material. In the application, fluorine atoms are introduced into the Fe-N-C material to produce axial coordination with Fe of the FeN4 center, the fluorine element with high electronegativity can effectively improve the isoelectric point of the Fe-N-C material, the reaction activity of the material is enhanced, the Fe leaching of the material in the reaction process is inhibited, and the stability of the material is improved. In addition, the prepared fluorine-doped Fe-N-C composite material can be reused through fluorine-doping regeneration, and high reduction activity and stability can be maintained.

The invention discloses a nickel-phosphine co-doped molybdenum disulfide composite material as well as a preparation method and application thereof. According to the method, nickel ions and organic phosphonic acid molecules are co-doped into the structure of molybdenum disulfide, and the nickel-phosphine co-doped molybdenum disulfide composite material with high stability and catalytic performance is prepared by fully utilizing the good conductivity of molybdenum disulfide, the chemical modification function of organic phosphonic acid and the strong oxidation-reduction activity of the nickel ions. The composite material shows excellent catalytic performance in the aspect of catalytically activating peroxymonosulfate to oxidize and degrade organic pollutants, can effectively degrade the organic pollutants in wastewater, and has the advantages of mild reaction conditions, high degradation rate, high catalytic stability, high pollution resistance, high reusability and wide application prospect.

The invention belongs to the technical field of electro-catalysis, and particularly relates to an electrode for synthesizing RT base as well as a preparation method and application thereof. The electrode comprises a substrate and active components loaded on the surface of one side of the substrate, wherein the active components comprise copper and lanthanum. The electrode is a solid polymer (SPE) electrode, active components of copper and lanthanum are loaded on the surface of a substrate, a catalyst is arranged on the electrode at zero interval, and power consumption is greatly reduced. According to the present invention, the active component copper has high selectivity, the lanthanum can improve the catalytic activity and the durability and the service life of the electrode, the electrode is used for synthesizing the RT base, the reduction activity of the electrode is high, the use stability is strong, and the efficient and stable performance can be maintained during the long-time electrolysis process.

The invention discloses a composite catalyst as well as a preparation method and application thereof. The composite catalyst comprises carbon nitride, cobalt sulfide and phosphorus. The composite catalyst provided by the invention utilizes the synergistic effect between carbon nitride and cobalt sulfide to regulate the electron and chemical structure of an active center and promote the generation and migration of photo-generated charges at the same time. The surface of the catalyst is modified by phosphorus, so that adsorption and activation of reactants CO2 and H2O molecules can be further promoted. According to the preparation method of the composite catalyst, the synthesis strategy is regulated and controlled, the cobalt sulfide is uniformly dispersed on the carrier, and the reduction activity and stability of carbon dioxide are improved. The catalyst is low in price, the preparation process is simple, the repeatability is good, and large-scale production is easy to carry out.

The present invention develops a method for preparing NPTS@PANI by coating NPTS with polyaniline and its application in the photocatalytic reduction of hexavalent chromium, which belongs to the field of composite material preparation and photocatalytic reduction. The preparation of the composite material NPTS@PANI is divided into two steps, including the preparation of organic hybrid metal selenide NPTS and in-situ coating of polyaniline. The material exhibits excellent photocatalytic activity in an acidic environment (pH=3), has efficient photocatalytic reduction activity for high-concentration Cr(VI) solutions, and has good reusability and cyclic stability. Under different water sources or sunlight irradiation conditions, the material also exhibits excellent photocatalytic reduction performance for Cr(VI).

The invention provides an atomic-scale Ag cluster functionalized MOF (Metal Organic Framework)-based composite electrocatalyst as well as a preparation method and application thereof. The catalyst is named as Ag (at) MOF-Ag4-2Ph. The catalyst is prepared by a one-step method at room temperature, and the specific steps are as follows: stirring a mixed solution of a triazole derived ligand, silver nitrate and ammonia water at 25 DEG C, centrifuging the reaction solution after the reaction is finished, and performing vacuum drying to obtain the electrocatalyst. The catalyst has superfine Ag nano-particles generated by triazole derived ligands in situ, Ag monatomic and Ag4 atomic cluster active sites, and the three components have a synergistic effect, so that excellent electrocatalytic CO2 reduction activity is realized. The catalyst can realize full-pH electrolysis and maintain high selectivity and high current density to CO in an extremely wide voltage range. The method is an Ag-based industrial-grade high-performance electrocatalyst which is green, simple and convenient to synthesize and easy to produce on a large scale, a green example is established for an industrial CO2 electrolysis system, and the method has important practical application value in the aspects of industrial flue gas CO2 recovery and the like.

The invention discloses a zirconium-doped nano zero-valent metal composite material as well as a preparation method and application thereof. The preparation method comprises the following step: in an aqueous solution, reacting transition metal salt with a zirconium source under the action of a reducing agent to prepare the zirconium-doped nano zero-valent metal composite material. The zirconium-doped nano zero-valent metal composite material is prepared through a liquid-phase in-situ reduction coprecipitation method, and the composite material has extremely high stability while showing excellent oxidation-reduction activity. Meanwhile, the composite material can be used as a Fenton-like catalyst to efficiently treat wastewater polluted by the organic chelating agent.

The invention belongs to the technical field of polymer electrolyte membrane fuel cells, and provides preparation and application of a template-assisted derived electrocatalyst, metal macrocyclic compound self-assembly is performed on the surface of a metal organic framework material to form an ordered aggregate, and then high-temperature heat treatment is performed on the composite to prepare the corresponding electrocatalyst. The electrocatalyst prepared by the method does not form metal-based particles after being subjected to high-temperature heat treatment, so that metal aggregation is effectively avoided, the metal-nitrogen-carbon oxygen reduction active site density is improved, and the electrocatalyst has better oxygen reduction activity and stability in acidic and alkaline electrolytes. The preparation process of the catalyst adopted in the method does not need any acid treatment, the raw materials are rich in source, resources are saved, the cost is reduced, meanwhile, the preparation process of the non-noble metal electrocatalyst is simplified, and the prepared electrocatalyst has high oxygen reduction activity and durability and can be used in the field of polymer electrolyte membrane fuel cells.

The invention discloses an Ag / Cu2O / g-C3N4 heterojunction photocatalyst as well as a preparation method and application thereof, and belongs to the technical field of photocatalytic materials. The Ag / Cu2O / g-C3N4 heterojunction photocatalyst is prepared from the following components in percentage by mass: 10 to 30 percent of Cu2O. A g-C3N4 precursor prepared through a solvothermal reaction is fired into a nanotube shape in a tubular furnace, then Ag is generated in situ through heating and stirring, finally the Ag / Cu2O / g-C3N4 heterojunction photocatalyst is synthesized through heating and stirring, and the Ag / Cu2O / g-C3N4 heterojunction photocatalyst can be applied to the field of photocatalytic reduction of CO2. Compared with an existing photocatalyst, the Ag / Cu2O / g-C3N4 heterojunction has good yield and stability, and a strong built-in electric field at the heterojunction interface can accelerate separation and transfer of carriers and enhance adsorption and activation of CO2, so that the activity of photocatalytic reduction of CO2 is enhanced.

The present invention provides a catalyst for electrochemical oxygen reduction, comprising: nanoparticles containing platinum, and at least one selected from a group consisting of a specific polymer with a melamine compound as a monomer and a specific melamine compound. The catalyst for electrochemical oxygen reduction not only has high oxygen reduction activity (small overvoltage) but also has high durability at a practical temperature condition of 70 to 85°C.

The invention relates to the technical field of photocatalytic materials, and provides a preparation method and application of a Zn QDs / ZnWO4 photocatalytic material. The method comprises the following steps: (1) in the presence of a first solvent, mixing zinc acetate and sodium tungstate, and carrying out hydrothermal reaction to obtain a zinc tungstate photocatalytic material; and (2) in the presence of a second solvent, mixing zinc acetate and the zinc tungstate photocatalytic material, reacting under the condition of mercury illumination, and then drying in vacuum to obtain the Zn QDs / ZnWO4 photocatalytic material. The photocatalytic material shows excellent photocatalytic reduction activity on Cr (VI), the purification efficiency of the photocatalytic material on Cr (VI)-containing wastewater after illumination for 40 min reaches up to 99%, and the photocatalytic reduction efficiency of the Zn QDs / ZnWO4 photocatalytic material on the Cr (VI)-containing wastewater can still be kept at 96% or above after ten times of cycle experiments.

The present invention discloses a novel composite heterojunction photocatalyst, a preparation method thereof, and its application in carbon dioxide reduction. The photocatalyst is prepared by a hydrothermal method using WCl6 as the tungsten source, thioacetamide (TAA) as the sulfur source, cobalt phthalocyanine as the CoPc source, phosphoric acid (H3PO4) as the phosphoric acid source, and deionized water (H2O) as the solvent. The prepared (CoPc-P / WS2) photocatalyst has a spherical structure with a diameter of about 500 nm, and the surface contains rich functional groups, and it exhibits excellent photocatalytic CO2 reduction activity under visible light.

The present invention provides a Bi 2‑x Eu x WO6 / Nb2C MXene photothermal material and its preparation method and application, the preparation method comprises: dissolving Bi(NO3)3, Eu(NO3)3 and Na2WO4 in ethylene glycol to obtain a reaction precursor solution, performing a hydrothermal reaction to obtain Bi 2‑ x Eu x WO6; Nb2C MXene powder was dispersed in ethanol to obtain suspension A; Bi 2‑x Eu x WO6 was dispersed in ethanol to obtain suspension B; suspension A and suspension B were irradiated with ultraviolet light respectively, then suspension A was slowly added to suspension B, and the obtained mixed suspension was irradiated with ultraviolet light to obtain Bi 2‑x Eu x WO6 / Nb2C MXene photothermal material. 2‑x Eu x WO6 / Nb2C MXene photothermal material improves the photothermal catalytic CO2 reduction activity and methane selectivity.

The invention belongs to the technical field of catalysts, and particularly relates to a CoS / CuCo2S4 photocatalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: respectively dissolving Co (NO3) 2.6 H2O and Cu (NO3) 2.3 H2O in ethylene glycol to respectively obtain a first solution and a second solution; dropwise adding the second solution into the first solution while stirring to obtain a third solution; the preparation method comprises the following steps: adding CuCo2S4 into a reaction kettle, continuously stirring, then adding sodium dimethyl dithiocarbamate to obtain a suspension, and carrying out hydrothermal reaction, washing and drying to obtain the CoS / CuCo2S4 photocatalyst. According to the invention, a CS / CCS hollow spherical II-type heterostructure with rich sulfur vacancies and interface Co-S bond connection is constructed through a one-step hydrothermal method. An interface Co-S bond serves as an atomic channel to effectively promote separation and transmission of photon-generated carriers, a large number of photo-generated electrons are enriched on the surface of CCS and stably exist at active sites, and therefore the CO2 photo-reduction activity is improved.

The invention discloses a BiOCl / TiO2 photocatalyst prepared by an electrochemical method as well as a preparation method and application thereof, and the preparation method of the BiOCl / TiO2 photocatalyst comprises the following steps: 1) placing a Ti sheet subjected to surface pretreatment in an aqueous solution containing F <-> for anodic oxidation, and then placing the Ti sheet in a muffle furnace for heat treatment to obtain an anatase type TiO2 nanotube; 2) taking the TiO2 nanotube as a working electrode, and obtaining Bi nanocrystals in a water solution containing Bi (NO3) 3 with a certain concentration, lignin calcium benzenesulfonate and an emulsifier OP-10 by adopting a pulse electrodeposition method; 3, the sample with the Bi nanocrystals deposited is subjected to electrooxidation in a Cl <-> solution under the specific pH condition, and the BiOCl / TiO2 photocatalyst is obtained.The BiOCl / TiO2 photocatalyst prepared through the electrochemical method has the advantages of being stable in structure, high in CO2 photocatalytic reduction activity and high in product selectivity.

The invention particularly relates to a medium-entropy alloy material, a preparation method thereof, a modified electrode containing the medium-entropy alloy material, an electrochemical sensor containing the medium-entropy alloy material and application. The preparation method of the medium-entropy alloy material comprises the following steps that three metal elementary substance raw materials are mixed according to the molar ratio of 1: 1: 1, the mixture is placed in a vacuum smelting furnace to be smelted, and the medium-entropy alloy material is obtained; the three metal elementary substance raw materials are any three of Ni, Al, Mo, Fe, Cr, Al and Co. The modified electrode comprises a substrate electrode and the medium-entropy alloy material, and the medium-entropy alloy material is modified on the surface of the substrate electrode. The invention also provides application of the modified electrode in an electrochemical sensor and the electrochemical sensor containing the modified electrode. The medium-entropy alloy material shows good catalytic reduction activity on p-nitrophenol, and an electrochemical sensor constructed based on the medium-entropy alloy material is applied to detection of p-nitrophenol, so that a good analysis effect is achieved.

This invention belongs to the fields of catalytic chemistry and fine chemicals, and discloses a halogen-modified supported noble metal catalyst and its application in the synthesis of oxaragoli key intermediates. The catalyst uses alumina or modified alumina as a support, loads the active component (noble metal), and modifies its surface electronic structure through halide ions. The preparation method includes precursor conversion of the support, impregnation and reduction of the active metal, and post-modification and regulation of halide ions. The catalyst obtained by this invention exhibits excellent hydrogenation reduction activity and selectivity for compounds containing C=N or C≡N bonds under mild conditions. Under room temperature and low-pressure hydrogen conditions, this catalyst can efficiently catalyze the conversion of 2-fluoro-6-trifluoromethylbenzaldehyde oxime to the oxaragoli key intermediate 2-fluoro-6-trifluoromethylbenzylamine, showing promising industrial application prospects.

The invention belongs to the technical field of heavy metal wastewater treatment and environmental restoration, and discloses a method for efficiently reducing and removing hexavalent chromium (Cr (VI)) based on the synergistic effect of a plant-derived soluble organic matter (DOM, a water-soluble organic carbon compound passing through a 0.45-micron filter membrane) and a low-temperature freezing technology. According to the method, the plant source DOM is combined with freezing and thawing cycles for the first time, the reduction activity is enhanced through organic molecule protonation in an acid environment, the local concentration of Cr (VI) and DOM is increased by 10-100 times through low-temperature (lower than or equal to-15 DEG C) freezing, and the reaction rate is increased by 2-3 orders of magnitude. Experiments show that under the conditions that DOM is equal to 15.0 mg / L, pH is equal to 3.0 and freezing and thawing are performed for 2-3 times, the removal rate of Cr (VI) within 30 minutes reaches 99.7%, the efficiency is improved by 75% compared with normal-temperature treatment, and the effluent concentration is lower than 0.5 mg / L. The method does not need additional reagents, utilizes agricultural wastes, has high efficiency, low cost and environmental friendliness, is suitable for chromium-containing wastewater treatment in electroplating, leather making and the like, and has high efficiency, economical efficiency and ecological friendliness.

The invention discloses an aggregation-induced emission photocatalyst as well as a preparation method and application thereof, and belongs to the technical field of preparation of compounds. The structural formula of the aggregation-induced emission photocatalyst is as shown in formula I, wherein R1 is F or Cl; r2 is a diphenylamino group, a substituted diphenylamino group, a triphenylamino group or a substituted triphenylamino group; and R3 is Br, a substituted diphenylamino group, a triphenylamino group or a substituted triphenylamino group. The photocatalyst has visible light absorption, aggregation enhanced luminescence and reduction activity. According to the preparation method, a 4, 7-dibromobenzothiadiazole derivative and aromatic amine are subjected to Buchwald or Suzuki reaction, and the condition is mild. The catalyst is used for metal-free light-operated atom transfer radical polymerization, can efficiently catalyze the polymerization of acrylate monomers under the irradiation of a blue light or green light LED with a low dosage of 5-100 ppm, realizes high conversion rate, narrow distribution and block synthesis, is suitable for an aqueous phase system, and has good biocompatibility and large-scale prospects.