272 results about "Nano catalyst" patented technology

The invention discloses a modified graphite felt electrode for an all-vanadium redox flow battery and a preparation method of the modified graphite felt electrode, and belongs to the technical field of redox flow battery electrode materials. The preparation method comprises the following steps: graphite felt electrochemical oxidation etching treatment; self-assembling a conductive layer on the oxidized and etched graphite felt to obtain the graphite felt attached with the conductive layer; and loading a metal and nitrogen-doped carbon (M and NC) nano catalyst layer on the graphite felt attached with the conductive layer to obtain the modified graphite felt electrode. Various properties of the graphite felt are comprehensively improved through matrix treatment, structure change and load catalysis, mild electrochemical oxidation etching is adopted, a carbon fiber structure is protected, a self-assembled net-shaped conductive layer forms a stable conductive channel, the specific surface area is remarkably increased, a nitrogen-doped carbon shell is adopted to wrap metal nanodots to form an M-NC catalytic layer, and the specific surface area is remarkably increased. The catalyst layer is not easy to dissolve out, the capacity fading rate is obviously improved, the loading capacity of the catalyst layer on the reticular structure conducting layer with a larger specific surface area is larger, and meanwhile, the process is simple and low in cost.

The invention relates to the technical field of electrochemical sensors, and provides a multi-channel electrochemical detection electrode, an electrochemical sensor and a detection method.The multi-channel electrochemical detection electrode comprises an electrode substrate and a plurality of working electrodes arranged on the electrode substrate; the surfaces of the plurality of working electrodes are respectively modified with different types of metal nano-catalysts to detect different gas components, and the surfaces of the working electrodes are covered with PDMS hydrophobic layers to form a hydrophilic / hydrophobic channel separation structure. The surfaces of a plurality of working electrodes are modified with different types of metal nano-catalysts and covered with PDMS hydrophobic layers to form a hydrophilic / hydrophobic channel separation structure, and the multi-channel electrochemical detection electrode separates gas molecules through hydrophilic / hydrophobic channels, so that the cross reaction can be inhibited, and the cross sensitivity can be reduced.

The invention provides an efficient chloramphenicol degradation method based on Co-Cu-carbon composite nano-catalyst activated peroxymonosulfate, which comprises the following steps: regulating the Co / Cu molar ratio in a bimetal organic framework precursor, and performing pyrolysis to prepare the Co-Cu-carbon composite catalyst with an optimized pore structure, graphitization degree and metal dispersity; peroxymonosulfate is activated by utilizing the synergistic effect of Co / Co and Cu / Cu redox pairs to generate sulfate free radicals, hydroxyl free radicals, singlet oxygen and superoxide free radicals, and direct oxidative degradation of chloramphenicol is promoted by taking a catalyst as an electron transfer bridge; the method realizes rapid and efficient removal of chloramphenicol, high mineralization rate, excellent cycle stability and strong anti-interference capability, and solves the technical problems of low removal efficiency, high cost and easy secondary pollution in the prior art.

The invention discloses a method and a device for preparing a single-walled carbon nanotube based on the host-guest interaction of pillararene and metallocene. The method comprises the following steps: enabling a host compound and a guest compound to form a host-guest complex; the host compound comprises pillararene or a derivative thereof, and the guest compound comprises a cyclopentadienyl metal complex or a derivative thereof; the method comprises the following steps: reacting a mixed reaction system containing a host-guest compound and a polymerization inhibitor at a high temperature to obtain nano-scale catalyst particles; and contacting the nano-catalyst particles with a carbon source, and decomposing and growing the carbon source on the surfaces of the nano-catalyst particles to prepare the single-walled carbon nanotubes. The method disclosed by the invention is mainly based on the strong inclusion behavior of the host compound and the guest compound, and by utilizing the compatibility of the host compound, the solubility of the metallocene in an organic solvent is effectively improved, the decomposition time of the metallocene at high temperature is prolonged, and the in-situ controllable preparation of nano-scale catalyst particles is achieved; and furthermore, the yield and the quality of the single-walled carbon nanotubes are improved.

The invention discloses a non-noble metal catalyst, a preparation method thereof and application of the non-noble metal catalyst in preparation of acetic acid through methane oxidation, and belongs to the field of direct conversion and utilization of methane. The active metal of the catalyst is transition non-noble metal MnOx, and the carrier is an MFI type molecular sieve (ZSM-5). The catalyst can directly react methane and oxygen at low temperature to prepare acetic acid without adding a co-reducing agent and carbonylation raw materials (such as H2 and CO). The nanometer MnOx catalyst has the advantages of mild reaction conditions, high acetic acid selectivity and the like, the acetic acid selectivity can reach 81.8%, and the nanometer MnOx catalyst shows good recycling stability.

The utility model provides a copper-based nano-catalyst production device and relates to the technical field of copper-based nano-catalysts. The device comprises a supporting seat, a first-stage grinding cylinder, a second-stage grinding cylinder, a third-stage grinding cylinder and a material cylinder which are rotatably arranged above the supporting seat, are in a coaxial state and are sequentially communicated, and three baffles which are respectively arranged between the first-stage grinding cylinder and the second-stage grinding cylinder, between the second-stage grinding cylinder and the third-stage grinding cylinder and between the third-stage grinding cylinder and the material cylinder are arranged on the supporting seat. The two ends of the first-stage, second-stage and third-stage grinding cylinders and the material cylinder are rotationally connected with the corresponding baffles or supporting seats respectively; a first-stage screen is arranged on the baffle between the first-stage grinding cylinder and the second-stage grinding cylinder, a second-stage screen is arranged on the baffle between the second-stage grinding cylinder and the third-stage grinding cylinder, and a third-stage screen is arranged on the baffle between the third-stage grinding cylinder and the material cylinder. According to the utility model, three-stage grinding of materials is realized, the three-stage grinding is carried out in the same equipment, and material transfer is not needed among the multi-stage grinding, so that the grinding efficiency is greatly improved.

The invention provides a sludge-based composite fuel as well as a preparation method and application thereof. The sludge-based composite fuel is prepared from the following raw materials in percentage: 40-60% of dewatered sludge, 20-40% of biomass powder, 3-8% of a nano catalyst and 2-5% of a composite adhesive. According to the sludge-based composite fuel, sludge, biomass and other fuels are mixed according to a certain proportion, the nano-catalyst is added to improve the combustion performance of the sludge fuel, the composite adhesive enhances the forming strength and waterproofness of the fuel, the component proportion and process conditions are optimized, and the sludge-based composite fuel is prepared. The problems that traditional sludge fuel is low in heat value, poor in combustion stability, high in pollutant emission and insufficient in forming storage performance are solved.

The invention discloses a preparation method of a controllable Co-Cu bimetallic oxide nano-catalyst, and the controllable Co-Cu bimetallic oxide nano-catalyst is applied to electro-catalysis, so that low-concentration nitrate pollutants in high-salinity wastewater can be efficiently removed. According to the preparation method, a constant-voltage electrodeposition method is utilized, the atomic-scale dispersed Co-Cu double-active-site catalyst is constructed on a foamed nickel substrate, and the prepared bimetallic Co-Cu active-site catalyst can remove low-concentration nitrate pollutants efficiently and highly selectively and is suitable for purification of nitrate wastewater with a wide pH range and different concentrations. The method is easy to operate, high in stability and good in electrocatalytic activity, and a reliable solution with practical application potential is provided for green low-carbon electrocatalytic purification of high-salt nitrate wastewater.

The invention relates to the technical field of nano-catalysts, and discloses a preparation method and application of a ZnxCd1-xS nano-catalyst rich in sulfur vacancies, the preparation method of the ZnxCd1-xS nano-catalyst rich in sulfur vacancies is characterized by comprising the following steps: S1, mixing cadmium salt, zinc salt and thiourea in deionized water to obtain a mixed solution; and S2, putting the mixed solution into a reaction kettle for heating reaction, cooling, collecting a reaction product, washing the reaction product with deionized water, and drying the washed reaction product to prepare the ZnxCd1-xS nano-catalyst. The ZnxCd1-xS nano-catalyst synthesized by the method is uniform in dispersion, uniform in size and regular in morphology, the morphology of the obtained ZnxCd1-xS nano-catalyst is evolved into a litchi-shaped transition state with a rough surface from a spherical shape along with the rise of the reaction temperature, and then a pine tree-shaped morphology with the regular morphology is generated. In addition, the prepared catalyst is rich in certain sulfur vacancies, and the performance is remarkably improved when the catalyst is applied to the field of photocatalytic hydrogen evolution.

A method for preparing a transition metal electrochemical catalyst according to an embodiment of the present disclosure includes dissolving a nitrogen precursor and a transition metal precursor in a polyol-based solvent so as to prepare a solution in which transition metal ions and free anions are coordinated, and mixing same with a support so as to prepare a mixture, igniting the mixture so as to carbonize the polyol-based solvent, thereby forming transition metal nanoparticles encompassed by carbon, performing heat treatment in order to carbonize remaining organic matter contained in the mixture, and removing, through acid treatment, impurities and transition metal nanoparticles not encompassed by carbon, and then removing remaining acid through washing and additional heat treatment, thereby a nanocatalyst having a structure in which a single-atom transition metal-nitrogen bonding structure and / or transition metal nanoparticles encompassed by carbon exist is synthesized.

The invention relates to the technical field of catalysts, in particular to a nano-catalyst for preparing methane through hydrogenation of carbon dioxide, the nano-catalyst is prepared from a eutectic solvent as a carrier precursor through a coprecipitation method, the nano-catalyst comprises a carrier, and NiO is loaded on the carrier; on the basis of the total mass of the nano-catalyst, the content of NiO is 5-20 wt%, and the content of the carrier is 80-95 wt%; the average particle size of the nano-catalyst is 5-10 nm; the carrier is selected from one or more of CeO2, ZrO2, MgO and Al2O3. According to the nano-catalyst, the dispersity and stability of NiO particles are effectively enhanced by using the eutectic solvent as a carrier precursor and a solvent, high-density Ni-OV interface sites are constructed in situ by using an alkali treatment method, the adsorption and activation of the catalyst on H2 and CO2 are promoted, the higher CO2 conversion rate is shown, and the catalyst has a good application prospect. The catalyst for efficiently obtaining a single product CH4 at a low temperature and with high selectivity has a higher application value.

The invention discloses a preparation method of a Ru-WO3 nano-catalyst and a product and application of the Ru-WO3 nano-catalyst, the preparation method of the Ru-WO3 nano-catalyst comprises the following steps: adding ammonium metatungstate into deionized water, stirring to obtain a solution A, then adding citric acid into the solution A to obtain a solution B, mixing the solution B and a titanium felt, and carrying out hydrothermal reaction to obtain a WO3-x carrier; the preparation method comprises the following steps: dipping a WO3-x carrier in a RuCl3 aqueous solution to obtain a Ru-WO3-x precursor; the Ru-WO3-x precursor is subjected to calcination, and a Ru-WO3 nano catalyst is obtained; the mass ratio of the ammonium metatungstate to the citric acid is 2.4 to 10. The Ru-WO3 nano-catalyst prepared by the preparation method is high in activity and selectivity, and is beneficial to improving the synthesis efficiency of electrically driven ethylene glycol.

The invention relates to the technical field of separation and extraction, and provides an extraction method and application of chlorogenic acid in honeysuckle. The invention relates to a method for extracting chlorogenic acid from honeysuckle, which comprises the following steps: mixing honeysuckle powder with an ethanol solution, and carrying out ultrasonic enzymolysis; carrying out suction filtration to obtain a supernatant A containing chlorogenic acid and medicine residues I, and adding an ethanol solution into the medicine residues I to carry out microwave extraction; performing suction filtration to obtain a filtrate B and medicine residues II, mixing the medicine residues II with a citric acid-sodium citrate buffer solution, adding a Fe3O4-coated GO-coated MOFs nano-catalyst, performing hydrothermal reaction, performing suction filtration to obtain hydrolysate, and combining the hydrolysate with the supernate A and the filtrate B to obtain a total extraction solution; concentrating the total extracting solution under reduced pressure, and recovering ethanol until the volume of the concentrated solution is about 1 / 6-1 / 8 of the original volume; and concentrating under reduced pressure to thick paste, and drying to obtain the chlorogenic acid. The extraction efficiency and yield of chlorogenic acid are improved, and the utilization rate of raw materials and the product purity are improved.

The invention discloses a method for purifying water by catalyzing ozonation through a nitrogen-fluorine co-doped carbon-loaded cobalt nanomaterial. Co-ZIF-8 and polytetrafluoroethylene (PTFE) are respectively used as a precursor and a fluorine source, and the nitrogen-fluorine co-doped carbon-loaded cobalt nano-catalyst is successfully prepared through an etching synchronous doping strategy. The composite material can be used for catalyzing ozone to degrade organic pollutants in water. Nitrogen doping can promote formation of a metal-nitrogen coordination structure, and decomposition of ozone on the surface of the catalyst is facilitated. Fluorine modification can significantly enhance the hydrophilicity of the composite material and accelerate the solid-liquid reaction of ozone in a solution and a catalyst interface, and the strong electron withdrawing effect of fluorine can effectively adjust the electronic structure of the catalyst and promote the generation of strong oxidizing active oxygen species, thereby achieving efficient and rapid removal of pollutants. The water treatment method solves the problem of low ozone utilization rate in a conventional catalytic ozonation process, has the advantages of high reaction rate and stable treatment effect, and has a good application prospect.

The invention provides a heavy metal contaminated soil remediation effect evaluation method and system.The method comprises the steps that firstly, the heavy metal effective state content, microbial index data, plant index data and heavy metal ion migration data of a monitoring area are collected; calculating a repair efficiency index by using the first three types of data, exciting a nano-catalyst by microwave energy to generate active oxygen to catalyze the form transformation of the heavy metal, and recording temperature rise curve data in the reaction process; calculating a current density value of each monitoring point based on the ion migration data and generating a spatial distribution diagram; and fusing the remediation efficiency index, the temperature rise curve and the current density distribution data, inputting the fused data into a convolutional neural network, and finally outputting a soil remediation effect grade evaluation result and a spatial difference analysis result. According to the method, the accuracy and comprehensiveness of heavy metal contaminated soil remediation effect evaluation are improved.

The invention relates to a method for treating printing and dyeing wastewater. The method comprises the following steps: neutralization regulation, primary filtration for removing scum, decoloration and flocculation, secondary filtration, pH regulation, catalytic degradation under visible light, MBR membrane treatment and discharge. The printing and dyeing wastewater treatment process provided by the invention is compact in link, the first-stage filtration, decoloration flocculation and second-stage filtration in the treatment process all adopt conventional technical means in the field, the operation is simple and convenient, the cost is low, and a special bismuth-based aerogel composite material is used as a catalyst for photocatalytic degradation at the rear end; the aerogel is prepared by cross-linking a modified graphene oxide / BiOCOOH composite photocatalyst with an acrylic polymer matrix and then carrying out supercritical drying, so that macroscopic immobilization of a nano catalyst is realized. According to the method, the technological process is compact, the cationic dye which is difficult to biologically treat can be efficiently degraded, the industrial problems that a powder catalyst is easy to lose and difficult to recycle are solved, key indexes such as COD and chromaticity of the treated wastewater are remarkably reduced, and the treated wastewater can be discharged after reaching the standard.

The invention relates to the technical field of air pollution control, in particular to an air pollution denitration and desulfurization tail gas purification method which comprises the following steps: rotational flow spray desulfurization (adopting nanoscale composite absorbent slurry to efficiently absorb SO2 and remove particulate matters in a rotational flow reactor), two-stage catalytic denitration (using a nano-catalyst to promote NOx reduction in a low-temperature region, and using a high-temperature catalyst to remove the particulate matters in a low-temperature region). In the high-temperature area, a vanadium-tungsten-titanium-based catalyst is loaded through a novel honeycomb ceramic carrier to strengthen the reaction), deep collaborative purification is carried out (residual pollutants and aerosol are further removed by utilizing electrostatic precipitation and oxidative adsorption coupling), and an intelligent regulation and control system is used for optimizing the ratio of an absorbent, the temperature of the catalyst and flow velocity parameters in real time. According to the method, the problems of catalyst poisoning, high energy consumption and insufficient treatment efficiency in a traditional process are solved through a nano material modified absorbent, a temperature gradient catalytic reaction and a multi-pollutant synergistic removal mechanism. The desulfurization efficiency of the system is greater than or equal to 98%, the denitration efficiency is greater than or equal to 97%, the particulate matter emission is less than or equal to 10mg / m < 3 >, the SO2 is less than or equal to 35mg / m < 3 >, and the NOx is less than or equal to 50mg / m < 3 >

The application discloses a triazine ring synthesis method, and belongs to the technical field of medical intermediate synthesis. The method is characterized in that 2-methylaminothiourea and dimethyl oxalate are used as raw materials, a nanometer catalyst of scandium triflate (Sc(OTf)3) or ytterbium triflate (Yb(OTf)3) is loaded on magnetic Fe3O4@SiO2, a cyclization reaction is carried out in an organic solvent, the catalyst is separated and recovered through an external magnetic field after the reaction is completed, and high-purity triazine rings are obtained through acidification, crystallization and drying of the reaction liquid. The catalyst has the advantages of high specific surface area, high catalytic activity, easy magnetic separation and recovery, and can be reused more than 6 times. The product yield can reach 93% to 96%, and the purity is greater than or equal to 99.6%. The method realizes green, efficient and low-cost synthesis of triazine rings.

The invention relates to a preparation method of a trace Fe optimized Ru nano-catalyst and application of the trace Fe optimized Ru nano-catalyst in hydrodechlorination reaction of parachlorophenol. The preparation method comprises the following specific steps: firstly, dissolving ruthenium chloride hydrate and ferric trichloride into ethylene glycol, adding PVP (Polyvinyl Pyrrolidone) into the solution, fully mixing, adjusting the pH value of the solution to 3-4, transferring into a glass bottle, and heating and reacting in an oil bath pan at 180 DEG C; and centrifuging, washing and drying the obtained product to obtain a black powdery solid, namely the Ru-Fe nano-catalyst. The hydrodechlorination process is carried out in a double-chamber electrolytic tank separated by a Nafion 117 membrane, an electrolyte is a Na2SO4 solution, a Ru-Fe electrode taking carbon cloth as a carrier is used as a working electrode, a Pt sheet is used as a counter electrode, and an Ag / AgCl electrode is used as a reference electrode. The Ru-Fe nano-catalyst provided by the invention has the advantages of stable structure, uniform metal distribution and excellent electron synergistic effect, and can efficiently catalyze hydrodechlorination of p-chlorophenol and generate cyclohexanol. The preparation process is simple, convenient and environment-friendly, has a good industrial application prospect, and is particularly suitable for green treatment and resource conversion of chlorine-containing organic wastewater.

The invention discloses a Ni / TiO2 (at) C nano-catalyst as well as a preparation method and application thereof, and belongs to the technical field of catalysts. The preparation method comprises the following steps: mixing TiO2 (at) C powder, water and a nickel source precursor to obtain a suspension; and mixing the suspension liquid with a reducing agent, and carrying out a reduction reaction to prepare the Ni / TiO2atC nano-catalyst. The catalyst comprises a TiO2 (at) C nanosheet and Ni nanoparticles dispersed on the TiO2 (at) C nanosheet, wherein the average particle size of the Ni nano particles is 2.0 nm to 3.0 nm, and the content of the Ni nano particles is 12.8 wt% to 53.9 wt%. The catalyst shows excellent catalytic performance, 100% H2 selectivity and remarkable durability, and the TOF value of catalyzing ammonia borane to hydrolyze and produce hydrogen under the condition of no additive at 298 K reaches up to 253 min <-1 >.

The application discloses a method for preparing noble metal nanocrystals by a low-VOC polyol method, and belongs to the technical field of nanometer catalyst preparation. The method uses high-boiling polyol with a normal pressure boiling point not lower than 200 DEG C as a solvent and a reducing agent, adjusts the pH value of reaction slurry to 9-13 in a composite additive system containing a surface protecting agent and a pH regulator, and then carries out a reduction reaction at 160-200 DEG C through ultrasonic dispersion and programmed temperature rising to prepare supported noble metal nanocrystals. The application solves the VOC emission problem of the traditional method from the source by using high-boiling polyol. Meanwhile, the accurate control of nanocrystal size is realized through the synergistic effect of pH regulation and programmed temperature rising. The prepared catalyst has the advantages of uniform particle size, high dispersity and excellent catalytic performance. The method is stable in process, low in cost, green and environment-friendly, and suitable for large-scale production.

The present application relates to the technical field of catalytic hydrogenation reaction, and discloses a preparation method and application of an organic phosphine shell modified nanocatalyst, which comprises the following steps: adding a carbon carrier in an alcohol solvent and ultrasonic dispersion, then adding a chloroplatinic acid containing alcohol solution, and stirring at 0-15 DEG C; subsequently, an organic phosphine containing alcohol solution and a reducing agent are added, and the stirring is continued; finally, rotary evaporation is carried out, and drying is performed to obtain the nanocatalyst; the nanocatalyst is a platinum catalyst with a core-shell structure loaded on the surface of the carbon carrier. By introducing the organic phosphine ligand to the surface of the nanometer platinum particles, the core-shell structure nanoparticles with a flexible organic phosphine ligand modified shell are constructed, the adsorption and desorption strength and configuration of the active site electronic structure, the reaction microenvironment, the reactants and the intermediate state of the reaction interface are regulated, and the selective and efficient hydrogenation of the aromatic hydrocarbon containing nitro or carbon-carbon double bond is realized.

The application discloses a P and O co-doped FeNiRuOx nano catalyst and a preparation method and application thereof, relates to the technical field of electrocatalytic materials, and the catalyst takes Fe, Ni and Ru as metal active centers, reconstructs a surface electronic structure through P and O double anion co-doping, and forms a polygonal nano structure, wherein the mass fraction ranges of Fe, Ni, Ru and P are 5.0-6.0%, 75-78%, 11-12% and 6.5-7.0% respectively. The preparation method comprises the following steps: taking iron acetylacetone, nickel acetylacetone and ruthenium chloride trihydrate as metal sources, synthesizing a precursor through a solvothermal reaction, and realizing P and O co-doping through a sodium hypophosphite assisted solid-phase phosphorization process, and the preparation process is mild. The synthesized catalyst has unique structural advantages, the formed polygonal nano structure has a large specific surface area and rich grain boundary defects, more active sites are exposed, and convenient channels are provided for the mass transfer of reactants and products. The synergistic effect among the polymetals further enhances the catalytic performance.

The application belongs to the technical field of metallurgy, and discloses a high-purity raw material low-carbon silicon-manganese alloy precise smelting method. The method adds 0.1%-0.3% of nano CaO-Al2O3 composite catalyst in electrolytic manganese, silica and semi-coke raw materials, and then smelts in stages in an inert atmosphere ore-heating electric furnace after mixing and briquetting; the catalyst forms CaAl2O4 active phase at 1550-1650 DEG C, selectively adsorbs and activates SiO2, and reduces the reduction activation energy of SiO2 by 46.4%, while Fe2O3 is inhibited from reduction due to difficult adsorption. The application breaks through the inherent constraints of thermodynamics and kinetics in traditional silicon-manganese alloy smelting by constructing a nano catalyst-selective reduction technology paradigm, significantly reduces energy consumption and carbon emissions, and simultaneously realizes the multiple goals of low carbonization, high purification and greenization without sacrificing production efficiency.

The application discloses a preparation method of a binary transition metal aluminide nanocatalyst and application thereof. First, a mixed metal salt solution is mixed with an ammonium carbonate solution to obtain a metal oxide precursor through co-precipitation. Then, the oxide precursor is mixed with a low-temperature composite molten salt and is subjected to thermal reduction under a specific atmosphere. Through simple post-processing, a single-phase binary transition metal aluminide nanocatalyst with high catalytic activity is obtained. The non-noble metal aluminide nanocatalyst prepared is applied to a reaction of catalytically selectively hydrogenating acetylenes to prepare olefin compounds. Under mild conditions, 99% conversion of reactants is achieved while maintaining 96% olefin selectivity. Compared with a traditional supported catalyst, the metal aluminum atom greatly regulates the electronic and geometric structures of the transition metal atom, effectively improves the catalytic activity, and significantly improves the structural stability of the catalyst. The material has high phase purity, is easy to separate and recycle, and has good application prospect.

The present disclosure belongs to the technical field of catalyst preparation, and provides a polynorbornene / carbon black-cross-linked three-dimensional network-immobilized bimetallic copper / gold (PNBI / CB-Cu / Au) nanocatalyst, and a preparation method and use thereof. Metallic copper and gold both exist in a form of nanoparticles in the catalyst and are uniformly dispersed, and further enhancing a catalytic performance. Moreover, the carrier is a polynorbornene / carbon black-cross-linked three-dimensional network, and a relative content of free hydroxyl groups in the catalyst is controlled by changing a monomer ratio to adjust a hydrophilic-lipophilic balance value of the catalyst, adapting to a reaction of an organic phase with an aqueous phase. Furthermore, the catalyst is insoluble in conventional solvents, and has a desirable effect in immobilizing nanoscale metallic copper, prolonging a service life of the catalyst.

The invention discloses a rare earth element modified nickel-based nano-catalyst and a preparation method and application thereof.The rare earth element modified nickel-based nano-catalyst comprises a carrier and an active component loaded on the carrier, and the carrier is cerium dioxide and yttrium oxide co-doped three-dimensional ordered silicon dioxide nanoparticles; the active component is metal nickel. The application refers to the application of the catalyst in preparation of synthesis gas through carbon dioxide methane reforming. According to the invention, rare earth element doped and modified three-dimensional ordered silicon dioxide nanoparticles are used as a carrier, nickel metal is loaded on the nanoparticles, and the problem of carbon deposition can be effectively reduced by adjusting the interaction of alkaline sites and oxygen vacancies on the surface of the catalyst and the metal carrier. The method provided by the invention is helpful for realizing industrialization of a carbon dioxide methane catalytic reforming reaction, realizing a carbon emission reduction target and solving a green electricity energy storage problem.

The invention provides a copper-based composite catalyst and a preparation method and application thereof, and belongs to the technical field of metal catalyst preparation. According to the invention, the Cu / Cu2O / CuO nano-catalyst with abundant and tightly coupled Cu0 / Cu + interfaces is synthesized by using a simple wet chemical method. A heterogeneous interface of the catalyst has strong interface binding energy, agglomeration of Cu0 particles can be inhibited, Cu < + > can also be inhibited from being excessively reduced into Cu0, and dynamic oxidation-reduction balance is formed, in the reaction, the reduced Cu < + > can be re-oxidized into Cu < + > by dissolved oxygen CO2 in an electrolyte, the oxidized Cu0 can be re-reduced into Cu0 by electrons of an external circuit, the stability of the Cu0 / Cu < + > ratio at the interface is maintained, and the stability of the Cu0 / Cu < + > ratio at the interface is improved. Therefore, long-period stable operation of the catalyst is realized.

Provided herein are vesicular nanocatalysts decorated on their surface with enzymes, such as for industrial use. More particularly, the nanocatalysts include outer membrane vesicles (OMVs) presenting on their surface carbonic anhydrase or a functional fragment or derivative thereof. Uses, methods of manufacture, and compositions of the nanocatalysts are also disclosed herein.

The invention discloses a multistage porous graphite felt for a flow battery and a preparation method of the multistage porous graphite felt, and belongs to the technical field of chemical energy storage. The invention aims to solve the problems that the existing graphite felt electrode is low in catalytic activity and the catalyst is easy to fall off. The preparation method comprises the following steps: uniformly mixing thermosetting resin, a pore-forming agent and a bismuth-containing compound to prepare a precursor mixed solution; then immersing the graphite felt in the mixed solution for solvent heat treatment, so that the precursor uniformly permeates and is firmly attached to the surface of the graphite felt fiber; and performing high-temperature pyrolysis in an inert atmosphere. In the pyrolysis process, the resin is converted into a conductive porous carbon layer in situ, the pore-forming agent is decomposed to form rich multi-stage pore channels, and the bismuth-containing compound is reduced into a highly dispersed metal bismuth nano-catalyst by carbon thermal reduction and is confined in a porous carbon skeleton. The graphite felt electrode prepared by the invention has high catalytic activity, excellent mass transfer channels and high stability, and is simple in preparation process, controllable in cost and suitable for large-scale production.