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 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 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 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 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 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 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.