112results about How to "Increase catalytically active sites" patented technology

The invention provides a preparation method of a self-supporting ferronickel layered double hydroxide sulfide electrocatalyst. The preparation method comprises the steps of pretreating original foamednickel to obtain purified foamed nickel; dissolving nickel nitrate hexahydrate, iron nitrate nonahydrate and urea into deionized water according to a preset proportion to obtain a mixed solution, wherein the concentration of cations in the mixed solution is 40-45 mmol / L, and the concentration of urea in the mixed solution is 130-150 mmol / L; carrying out primary hydrothermal reaction on the mixedsolution to obtain NiFe LDH / NF; putting the NiFe LDH / NF into a thioacetamide solution, and carrying out a secondary hydrothermal reaction to obtain NiFe LDH-Sx / NF, wherein x is any number from 1 to 8.According to the preparation method of the self-supporting ferronickel layered double hydroxide sulfide electrocatalyst provided by the invention, the electrocatalyst shows excellent oxygen evolutionreaction catalytic activity under an alkaline condition, a ferronickel double hydroxide nanosheet structure directly growing on foamed nickel is beneficial to electron transfer, the catalytic surfacearea is increased, and the catalytic active sites are improved, so that diffusion of oxygen evolution reaction is facilitated.

The invention discloses a catalyst for ozone catalytic oxidation. The catalyst comprises: nitrogen-doped active carbon as a carrier, a main catalyst comprising two or a plurality of materials selectedfrom a Fe oxide, a Mo oxide, a Cu oxide, a Ni oxide and a Mn oxide, and a co-catalyst comprising one selected from a Ru oxide, a Pd oxide and a Pt oxide, wherein the mass fraction of the doped nitrogen is 1-20% relative to all the carrier, and the catalyst comprises 100 parts by weight of the carrier, 10-50 parts by weight of the main catalyst, and 1-10 parts by weight of the co-catalyst. According to the present invention, the catalyst can be used for various chemical industry sewage treatment fields, is used for reducing difficultly-degraded organic matters, cyanides and the like in sewage,is especially suitable for the field of deep treatment of coal chemical industry sewage and coking sewage, and can reduce the coking wastewater CODCr to less than 30 mg / L from 150 mg / L in the deep treatment of coking wastewater so as to achieve the circulation water reuse standard, wherein the CODCr removal rate can achieve more than 80%.

The invention discloses a synthesis method of vanadium-modified Ni3S2 electrocatalyst automatically assembled from a rodlike shape into a ball-flower shape. The synthesis method comprises the following steps that clean foamed nickel is dipped into turbid liquid with the vanadium source concentration being 5-30 mM and the mole ratio of a vanadium source to a sulfur source being (1) to (0.5-12), a microwave solvent thermal reaction is conducted, and after the sufficient reaction is completed, the vanadium-modified Ni3S2 electrocatalyst material automatically assembled from the rodlike shape intothe ball-flower shape is obtained. The method is easy to operate, the reaction condition is mild, the consumed time is short, the prepared vanadium modified Ni3S2 product automatically assembled fromthe rodlike shape into the ball-flower shape is high in purity, and uniform in shape and size. In order to achieve the above purpose, the following technical scheme is adopted.

The invention provides a preparation method of a carbon nitride / tungsten trioxide nano composite material. The preparation method comprises the following steps: (1) mixing and fusing deionized water and absolute ethyl alcohol, then stirring, adding sodium tungstate, stirring to dissolve at room temperature, adding a carbon nitride precursor, stirring, precipitating to obtain crystals, drying the crystals, grinding the crystals, and thus obtaining a white powder, wherein the carbon nitride precursor comprises urea and dicyandiamide; (2) calcining the white powder obtained in the step (1) to obtain a yellow solid, grinding the yellow solid, and collecting a yellow powder; (3) stirring the yellow powder obtained in the step (2) with HCl; and swashing away impurities, then filtering, drying, and grinding to obtain a yellow powder; and (4) calcining the yellow powder obtained in the step (3). The invention also provides the carbon nitride / tungsten trioxide nano composite material prepared by the method and an application thereof. The method is simple and easy to control, and friendly to the environment; the obtained nano composite material has high dispersion and high catalytic performance; and an electrode prepared from the nano composite material has high sensitivity.

The invention provides a synthetic method for 3D self-assembled flower-like vanadium-modified Ni3S2. The method comprises the following steps: immersing clean metal nickel into a suspension having a vanadium source concentration of 5-40 mM, a molar ratio of a vanadium source to a sulfur source of 1: (1-12), and a weakly acidic or weakly alkaline pH, and performing a microwave solvothermal reactionto obtain the 3D self-assembled flower-like vanadium-modified Ni3S2 electrocatalyst material after the reaction is fully performed. The method provided by the invention has simple operation, mild reaction conditions, short time consumption and a uniform morphology and size; and the material has a unique hierarchical structure, so that the catalytic activity of the material is increased, and the material can be used as an excellent electrocatalytic oxygen evolution electrocatalyst.

The invention discloses a mixed metal sulfide electrode and a preparation method thereof. The mixed metal sulfide electrode is composed of a central core layer and a peripheral shell layer, and is vertical to a conducting substrate to form a hierarchical array structure. The preparation method comprises the following steps: dissolving compounds containing iron, cobalt or nickel into a mixed water solution containing molybdenum and sulfur respectively, adopting a high-pressure hydrothermal method, and carrying out a one-step reaction on the conducting substrate material to obtain the mixed metal sulfide electrode. The hierarchical structure of the electrode is beneficial for improving the specific surface area of the electrode material and increasing the catalytic activity sites; the array structure is beneficial for improving the electron transfer efficiency of the electrode material and the diffusion of an electrolyte; and the adjustable electronic energy level is beneficial for effective injection of electrons from the electrode to the electrolyte. Through these advantages, the catalytic activity, stability and corresponding device performance of the mixed metal sulfide electrode are higher than those of a corresponding single metal sulfide electrode. The electrode prepared by the method can meet high-efficiency and low-cost energy conversion and the application requirement of storage devices.

The invention belongs to the technical field of solar cells and energies, and particularly relates to a preparation method of a porous nanocrystalline Cu2S counter electrode of a quantum-dot-sensitized solar cell. The preparation method comprises the steps of: regarding copper acetate and thioacetamide as precursors; obtaining 20-100 nm cuprous sulfide (Cu2S) nanometer particles through solvothermal reaction; preparing the cuprous sulfide (Cu2S) nanometer particles and ethanol into a thick liquid; forming 5-10 microns Cu2S nanocrystalline porous film on a conductive base body by utilizing a knife coating method, a silk screen print method or a spin-coating method; sintering at 300-500 DEG C in an inert atmosphere or vacuum for 10-60 min to obtain a battery electrode. The prepared Cu2S nanometer porous counter electrode extremely increases contact area of the counter electrode and electrolyte, further increases catalytic reaction site of the Cu2S and the electrolyte, and improves performance of the solar cell. In addition, the preparation method of the porous nanocrystalline Cu2S counter electrode of the quantum-dot-sensitized solar cell is simple in preparation technology, relatively low in cost and has wide application foreground and wide research values.

The invention belongs to the field of electrochemical energy and particularly relates to a preparation method of a cathode material for a lithium-air battery and the lithium-air battery. A Co3O4@Ni nanowire array prepared by using a hydrothermal process has larger specific surface area; porous structures and ideal specific surfaces of nanowires are obtained by the low-temperature calcination process, and further the contact area between electrolyte and an electrode is increased, therefore, more reactive sites are provided for ORR and OER processes. The surfaces of the nanowires become rough after the nanowires are soaked; with the rough surfaces, the specific surface area of the nanowires is increased and a greater storage space is provided for discharge products. In addition, Co3O4 is reduced after the nanowires are soaked, oxygen vacancies and surface defects are increased and catalytic active sites are also increased, so that reversible formation and decomposition of a weak crystalline film-like discharge product on the surface of a catalyst are favorably promoted, therefore, the integral performance of the lithium-air battery is significantly improved.

The invention discloses a preparation method for a catalyst made from a composite material, a product and an application thereof and belongs to the field of catalysts. The preparation method comprisesthe following steps: S1, preparing an amorphous alloy precursor of a mm / micro-porous structure by a 3D printing mode; S2, selectively corroding the amorphous alloy precursor of the mm / micro-porous structure by a corrosion solution by means of a chemical or electrochemical process to prepare a metal nano porous structure on the surface of the precursor so as to obtain a graded porous structural piece; and S3, executing surface modification on the graded porous structural piece to form a metal oxide or a metal sulfide so as to improve the catalytic performance of the graded porous structural piece, wherein one or more modes are adopted to execute surface modification. The invention also provides the catalyst prepared by the method. The catalyst can be applied to the field of sewage treatment and electro-catalysis. The method is simple and feasible, and the prepared catalyst is relatively good in effect.

The invention discloses a preparation method for a NiS2 / CoS2 counter electrode of a dye-sensitized solar cell. The preparation method comprises the steps of pouring a mixed solution containing potassium persulfate, nickel sulfate and ammonia water into glass ware loaded with an FTO conductive substrate, allowing the mixed solution to stand, performing washing and drying, and performing in-situ growth on an FTO surface to obtain a precursor; placing the precursor in cobalt nitrate solution for immersion, and taking out and drying the product; and respectively placing the FTO and a sulfur source which are immersed by the cobalt nitrate solution in a vacuum tubular furnace, rising a temperature to 350-550 DEG C under argon protection, performing heat preservation for 2 hours, and obtaining the NiS2 / CoS2 counter electrode after cooling. The preparation process for the NiS2 / CoS2 counter electrode, disclosed by the invention, is simple, a heterojunction of a nanosheet and nanoparticles is formed, the catalytic active sites of the electrode are added, a nanosheet structure growing perpendicularly is beneficial for diffusion of an electrolyte, the diffusion resistance is reduced, so that the NiS2 / CoS2 counter electrode has higher electrocatalytic activity, and the photoelectric conversion efficiency is improved.

The invention belongs to the technical field of water treatment, and provides a photocatalytic separation film for water treatment and a preparation method. The method includes the steps that nano TiO2 and nano ZnO are generated in situ in the synthesis process of tertiary butyl thio[4]calixarene, then the nano TiO2 and the nano ZnO are compounded with graphene, a nano TiO2-nano ZnO-calixarene -graphene composite photocatalyst is prepared and further added into a polyether sulfone spinning solution, and the photocatalytic hollow fiber separation film is prepared through spinning. Compared witha traditional method, by means of the prepared photocatalytic separation film, the problem of film contamination in the film separation technology and the problem about nano powder recovery in the photocatalysis technology are solved at the same time, the utilization rate of visible light is high, the photocatalysis efficiency is high, and a catalyst can be evenly dispersed.

The invention belongs to the technical field of material science and electro-catalysis and specifically relates to a method for compounding a ferronickel hydrotalcite nano-array compound structure byutilizing an in situ self-sacrificing template process. The method comprises the following steps: taking a ferro-nickel alloy as an electrode substrate and a reaction template; growing the ferronickelhydrotalcite nano-array compound structure, served as a catalyst for oxygen evolution reaction of electrolyzed water, on the ferro-nickel alloy by adopting the method for in situ self-sacrificing thetemplate. When the ferro-nickel alloy with the grown ferronickel hydrotalcite nano-array compound structure is placed into an electrochemical three-electrode test system and is used as an oxygen evolution electrode of electrolyzed water in an alkaline medium, efficient proceeding of oxygen evolution reaction of electrolyzed water under lower impressed voltage with high stability can be guaranteed. The preparation process according to the invention is simple; the required raw materials are low-cost and extensive in source; the method is cost-saving, is beneficial to industrial production and has a bright application prospect.

The invention discloses a preparation method of a highly doped nitrogen, phosphorus and carbon nano-sheet for efficient hydrogen production to improve the dosage concentration of heterogeneous atoms such as nitrogen and phosphorus in carbon materials, increase catalytic activity sites in the carbon materials and improve catalytic activity of the carbon materials. An appropriate proportion of nitrogen sources, carbon sources and phosphorus sources are dissolved, stirred, mixed, dried, pyrolyzed and the like to obtain the high-concentration nitrogen and phosphorus doped carbon nano-sheet. The preparation method has the advantages that raw materials are easily obtained, the technology is simple, operation is convenient, the preparation method is low in cost and environmentally friendly and the like. The whole reaction process is low in requirement for preparation equipment, industrial production is facilitated, the prepared materials have nitrogen and phosphorus with high dosage concentration, electro-catalysis hydrogen production performance is effectively improved, and the preparation method has practical industrial significance.

The invention relates to a three-dimensional orderly macroporous ferronickel phosphide material and preparation and application thereof. The material preparation process comprises the steps that (1) under the inert gas protective atmosphere, a potassium peroxodisulfate solid is added into constant-temperature deionized water, then methyl methacrylate is added, reacting is conducted, centrifuging and cleaning are conducted, evaporating is conducted for removing moisture, and thus a PMMA solid is obtained; (2) ferric nitrite and nickel nitrite are taken and dissolved into ethylene glycol, stirring is conducted, then methyl alcohol and ethylene glycol are added, the PMMA solid continues to be added, vacuum filtration is conducted after stirring, an obtained solid product is dried and calcined, and thus a ferronickel oxide is obtained; and (3) under inert gas protection, the ferronickel oxide and sodium hypophosphite are placed at a low air opening and an upper air opening correspondingly,calcining is conducted, and thus an objective product is obtained. Compared with the prior art, phosphatized ferronickel of a three-dimensional orderly macroporous structure is prepared successfullythrough a simple low-temperature phosphatization method, and the phosphatized ferronickel can serve as HER electrocatalyst to be applied to water electrolysis for hydrogen evolution, and has high catalytic activity, stability and the like.

The invention provides a P-O doped Fe-N-C nanosheet and a preparation method thereof, and belongs to the field of battery catalytic materials. The preparation method is characterized by, to begin with, forming Fe-N coordination; then, preparing a FeN4-containing carbon two-dimensional nanosheet through carbonization; and with a compound structure containing P-O bonds being as a precursor, carryingout high-temperature reaction to finally synthesize the P-O doped Fe-N-C nanosheet. Since the Fe-N coordination is formed firstly, the finally-prepared Fe atom load is greatly improved, and catalyticactive sites are increased; and secondary doping heat treatment in the preparation method facilitates further realization of the stable nanosheets. The P-O doped Fe-N-C nanosheet prepared by the method is used as a bifunctional catalyst, the catalytic performance and stability of which are superior to those of existing commercial Pt / C+IrO2 catalysts.

The invention provides an electrocatalyst ZIF-9 (III) / Co LDH nanosheet composite material and a preparation method thereof, and belongs to the technical field of electrocatalysis. The method comprisesthe following steps: respectively dispersing cobalt salt and benzimidazole into an N, N-dimethylformamide solvent, carrying out reflux reaction for a period of time at a certain temperature, finallycooling to room temperature, and then centrifuging, washing and drying to obtain ZIF-9 (I); mixing ZIF-9 (I) and cobalt salt and dissolving a mixture in a mixed solvent of absolute ethyl alcohol and ultrapure water, performing a reflux reaction, then performing centrifugal separation, washing and drying, and obtaining the ZIF-9 (III) / Co LDH composite material with the nanosheet morphology. According to the method, phase transformation of ZIF-9 and transformation from ZIF-9 to LDH are achieved at the same time, and compared with other composite materials, the method has the advantages that thecost is low, the reaction process is easy to control, and the electrocatalytic activity is more excellent, and the method can be suitable for industrial large-scale production.

The invention discloses a preparation method of a CoFe2O4 / AC microbial fuel cell air cathode catalytic material. The preparation method comprises the following steps: A, preparing an iron-cobalt liquid: weighing cobalt chloride and iron chloride, adding a mixed solution of deionized water and ethylene glycol, and stirring to obtain the iron-cobalt solution; B, weighing activated carbon, ultrasonically dispersing in the obtained solution and stirring; C, dropwise adding ammonia water to the obtained solution, sealing the opening of a beaker by a fresh-keeping film, rising temperature and stirring; D, transferring an obtained suspension to a reactor, putting in an electric oven after sealing, and reacting; E, collecting obtained products: taking the reactor out, filtering after cooling to room temperature, cleaning with ethanol and deionized water repeatedly, and placing in the electric oven to be dried overnight; F, placing obtained dried solid materials in a porcelain boat, putting in a tubular furnace, cooling to the room temperature to obtain a nanometer mixture, namely a CoFe2O4 / AC catalyst. The CoFe2O4 / AC microbial fuel cell air cathode catalytic material is simple in process, easy to control process parameters, low in cost, good in dispersion, more in active sites and obvious in catalytic performances.

The invention provides an electrocatalytic oxygen evolution electrode prepared from single-layer porous NiFe hydrotalcite as a catalytic active component. The single-layer porous NiFe hydrotalcite isshaped like nano-sheets, a lot of small holes are distributed in the nano-sheets, the nano-sheets have the relatively large specific surface area, a lot of edge positions are exposed, and catalytic active sites are greatly increased. The electrocatalytic oxygen evolution electrode shows the excellent activity in an alkaline medium, when the current density reaches 10 mA / cm<-2>, the overpotential is required to be 230 mV only, the Tafel slope is 47 mV / dec<-1>, and the electrocatalytic oxygen evolution electrode is obviously better than the electrochemical oxygen evolution performance of commercial IrO2. Besides, the raw materials of the electrocatalytic oxygen evolution electrode are wide in source, and the electrocatalytic oxygen evolution electrode is low in cost, has the long-term structural and chemical stability and is applicable to industrial use. A preparation method is easy to operate, conditions are mild, the required time is short, and large-scale production can be realized.

The invention provides a molecular sieve-based Ce-Mn oxide porous photocatalyst, and a preparation method and an application thereof, and relates to the technical field of nanomaterial photocatalysis.The porous photocatalyst contains a large amount of meso-pores, and the active components of the porous photocatalyst composed of cerium oxide and manganese oxide, wherein the manganese oxide existsin an amorphous state, the cerium oxide exists in a crystalline state, and cerium atoms in the cerium oxide are partially substituted by manganese atoms. The preparation method comprises the followingsteps: certain amounts of cerium acetate, manganese acetate and a molecular sieve are weighed, and are added into deionized water, heating and stirring are carried out until the added substances arecompletely dissolved, the obtained solution is stirred and reacted, and then is ultrasonically treated, solid particles in the solution are separated from the solution, and the obtained solid is driedat a low temperature, and then is calcined at a high temperature to prepare the molecular sieve-based Ce-Mn oxide porous photocatalyst. The molecular sieve-based Ce-Mn oxide photocatalyst of the invention has the advantages of increase of photocatalytic active sites, expansion of the visible light response range, inhibition of the regeneration of photogenerated charges, and improved visible lightphotocatalytic activity.

The invention relates to a preparation method of an ionic liquid modified nitrogen-sulfur co-doped graphene oxide composite material. The method comprises the following steps: preparing a dispersion liquid from graphene oxide and deionized water, then mixing 1-aminopropyl-3-alkyl imidazole bromide salt, potassium hydroxide and the graphene oxide dispersion liquid, carrying out a reaction process to obtain a 1-aminopropyl-3-alkyl imidazole bromide salt and graphene oxide composite product, then mixing the product with thiourea, adding a solvent to dissolve the mixture, and reacting at 160-200 DEG C to obtain the composite material. The composite material is loaded on a cathode electrode to serve as a catalyst. The material obtained by the invention has good oxygen reduction catalytic activity and a wide application prospect.

The invention belongs to the field of novel chemical materials and especially relates to a lanthanum cobaltate / attapulgite / reduced graphene oxide nano-structure composite material, a preparation method, and an application thereof. The preparation method includes the steps of: 1) preparing lanthanum cobaltate / attapulgite through a sol-gel process, adding the lanthanum cobaltate / attapulgite to deionized water and acidifying the liquid and regulating pH value to obtain a lanthanum cobaltate / attapulgite water solution carrying positive charges; 2) reducing graphite oxide with hydrazine hydrate to produce reduced graphene oxide carrying negative charges, and mixing the reduced graphene oxide with the lanthanum cobaltate / attapulgite water solution, stirring the mixture in water bath, performing a reaction, and drying a reaction product to obtain a perovskite / attapulgite / reduced graphene oxide composite material. With the composite material as a catalyst for performing photo-SCR denitration, conversion rate on NOx in a low-temperature zone (100-200 DEG C) can reach more than 95%.

The invention relates to a coated catalyst, a preparation method thereof and an application of the coated catalyst in a fuel cell. The inner layer of the coated catalyst is transition metal oxide nanoparticles, and the outer layer of the coated catalyst is a sulfur element and nitrogen element doped carbon coating layer. The sulfur, nitrogen and carbon doped and coated in the coated catalyst havethe effect of fixing the active sites of the catalyst while increasing the catalytic active sites, and cooperatively promote the oxygen reduction catalyzed reaction with the transition metal oxide nanoparticles, so that the coated catalyst has the better catalytic effect. Meanwhile, a compact oxidation film is easily formed on the surfaces of the transition metal oxide nano-particles after the high temperature treatment, in addition, a coating layer is also arranged on the surface, so that the coated catalyst has the better corrosion resistance. The catalyst with the coated structure has the better catalytic effect and higher corrosion resistance, the performance of the catalyst is superior to that of a commercial catalyst, and the preparation process is safe and environment-friendly, theflow is simple, the cost of used raw materials is lower, so that the coated catalyst has wide application prospect in the field of fuel cell catalysts.

A nickel-based catalyst for improving the performance of a direct borohydride fuel cell is characterized in that the catalyst is prepared according to the following simple method of: (1) preparing a NiSO4 solution of 0.2 mol / dm<3> at a normal pressure and a temperature ranging from 293.15K to 313.15K; (2) assembling a three-electrode system, namely placing a smooth Ni sheet (serving as a working electrode) of 2 square meters in the above solution, wherein the Ni sheet is taken as a counter electrode, and a silver / silver chloride electrode is taken as a reference electrode; and (3) depositing Ni on a metal nickel sheet to prepare the nickel-based catalyst by using a constant potential (-0.8V) method. The surface morphology of the catalyst is changed due to deposition of the Ni, the specific surface area is obviously increased, catalytic active sites are greatly increased, and thus, the direct oxidizability of BH4<-> is enhanced; and meanwhile, the charge transfer resistance of electrode reaction is further reduced due to the deposition of the Ni, and fuel discharging efficiency is obviously improved.

The invention provides a synthesis method of a vanadium modified Cu2S self-supported electrode material. The synthesis method comprises following steps: clean copper foam is immersed into a suspensionliquid for solvothermal reaction so as to obtain the V modified Cu2S self-supported electrode material via full reaction, wherein in the suspension liquid, a vanadium source concentration is controlled to be 10 to 40mM, the molar ratio of the vanadium source to a sulfur source is controlled to be 1:(1-10). The invention also discloses the vanadium modified Cu2S self-supported electrode material prepared using the synthesis method. According to the synthesis method, one-step solvothermal reaction is adopted for direct synthesis of the finished product, synthesis temperature is low, operation is simple, reaction conditions are mild, the raw materials are cheap and easily available, cost is low, yield is high, no subsequent processing is needed, the synthesis method is friendly to the environment, and is suitable for large scale production.

The invention discloses a method for preparing a metal-organic framework-based micro-membrane reactor, which includes the following steps: preparing a fiber membrane substrate; growing a metal-organicframework membrane on the fiber membrane; and assembling the fiber membrane having a metal-organic framework grown thereon to a micro-membrane reactor. Compared with a planar substrate, the fiber-based substrate provides larger surface area. Therefore, limiting or growing metal-organic framework nanoparticles to or on the fiber substrate can increase the surface area, thereby increasing the catalytically active sites. Further, the rough surface and the porous internal space of the fiber membrane can be regarded as microchannels, which promote the mass and heat transfer process of a catalyticreaction.

The invention relates to a preparation method and an application of a titanium dioxide heterojunction photoanode. The method comprises the following steps: (1) removing grease and dust on the surface of fluorine-doped tin oxide conductive glass; (2) adding the fluorine-doped tin oxide conductive glass treated in the step (1) into a hydrothermal solution, carrying out hydrothermal treatment, and thus obtaining rutile-phase titanium dioxide nanorods; and (3) adding the rutile-phase titanium dioxide nanorods into a solvent thermal solution, carrying out solvent thermal treatment, then rinsing with anhydrous ethanol, air-drying, carrying out annealing heat treatment, and thus obtaining the titanium dioxide heterojunction photoanode. With the titanium dioxide heterojunction photoanode as a photoanode and adopting of a three-electrode system, oxidative degradation of organic wastewater is carried out by utilizing simulated sunlight. Compared with the prior art, the prepared titanium dioxide heterojunction photoanode is a nano array, and has high-distribution heterostructure, higher specific surface area, larger active crystal face exposure, and stronger sunlight photoelectric catalytic activity.

The invention relates to a flue gas denitration catalyst and a preparation method thereof. The preparation method comprises the following steps: (1) preparing PVP (Polyvinyl Pyrrolidone) fibers by adopting an electrostatic spinning process, carrying out plasma treatment, putting the PVP fiber into a potassium permanganate solution, transferring the formed system into a reaction kettle, and carrying out hydrothermal reaction to obtain a PVP / MnO2 composite material with a three-dimensional core-shell structure; and (2) transferring the PVP / MnO2 composite material into a mixed solution containing zinc salt and ammonia water, conducting stirring, and then putting the stirred materials into a high-pressure reaction kettle to obtain a PVP / MnO2 / ZnO composite material, dissolving the PVP / MnO2 / ZnO composite material in ethanol, adding a nickel salt and a cobalt salt, dropwise adding ammonia water in a hydrothermal manner, carrying out a hydrothermal reaction to obtain a PVP / MnO2 / ZnO / NiCo2O4 composite material, soaking the composite material in NaOH, and carrying out calcination in an air atmosphere to remove a template to obtain the void / MnO2 / void / NiCo2O4 composite material. The catalyst has a relatively large specific surface area and good structural stability, and MnO2 and NiCo2O4 have a synergistic effect, so that the catalyst has relatively good catalytic activity.

The invention discloses a carbon-based acid anhydride synergistic transition metal denitration catalyst and a preparation method thereof. A mixture which is obtained through impregnation process ultrasonic dissolving of a transition metal and acid anhydride carbon (including graphene oxide, activated carbon, carbon nanotubes and charcoal) is calcined at 300-500 DEG C in inert atmosphere for 2-4 h to obtain a composite structure. The prepared catalyst highly-efficiently catalyzes NOx pollution gases at medium and low temperatures, the catalysis mechanism of the catalyst is characterized in that the reducing agent of a reaction is carbon, loading of the transition metal introduces high-activity metal acid sites, and the metal can promote the decomposition of acid anhydride groups on the surface of carbon in order to release a lot of catalysis activity sites, so the continuous and highly-efficient proceeding of the catalysis reaction is facilitated. The catalyst realizes the combination of the acid anhydride carbon material and the transition metal, fully shows the respective advantages of the acid anhydride carbon material and the transition metal, and can highly-efficiently process the NOx pollution gas at medium and low temperatures.

The invention relates to the field of semiconductor photocatalytic materials, in particular to an oxazinyl carbon-nitrogen polymer, and a preparation method thereof and application of the oxazinyl carbon-nitrogen polymer to serve as a photocatalyst. The oxazinyl carbon-nitrogen polymer is a heptazinyl-triazinyl carbon-nitrogen polymer which is of a rodlike structure and is spontaneously and directionally growing from a heptazinyl carbon-nitrogen polymer of a lamellar structure. The current carrier recombination rate of the oxazinyl carbon-nitrogen polymer is low, the rodlike structure can effectively capture luminous energy and bacteria, and the oxazinyl carbon-nitrogen polymer has excellent photocatalytic activity and stability, can be recycled, and has good actual application prospects.

The invention discloses a NaBH4 hydrogen production catalyst Co-CoOx@C-rGO and a preparation method thereof. The molecular formula of the catalyst is Co-CoOx@C-rGO, and the structure of the catalyst is a carbon-shell-coated Co-CoOx nano-particle growing on an rGO chip. The preparation method comprises the following steps: completely dissolving GO into ethanol; adding a water solution of metal saltCH4H6CoO4 into ethanol dispersion liquid of GO, and stirring in a water bath; adding a glucose water solution, stirring, transferring to a reaction, carrying out hydrothermal reaction and suction filtration, and cleaning with water and ethanol; carrying out freeze drying for 24 hours; and putting ground solids into a tubular furnace, and roasting at 550-750 DEG C for 1 hour in a nitrogen atmosphere, so as to obtain Co-CoOx@C-rGO. The prepared catalyst has very high catalytic activity to the catalytic hydrogen production of NaBH4.