84results about How to "Rich oxygen vacancies" patented technology

The invention relates to an ultrathin nanosheet array electro-catalytic material with a nano-porous structure and oxygen vacancies. The material is a cobaltosic oxide primary nanosheet array which grows vertically on a conductive substrate and is doped with a metal; an ultrathin nanosheet with oxygen vacancies and nanopores is obtained on each primary nanosheet; the conductive substrate is a titanium sheet or a foamed nickel sheet, and the doped metal is zinc, nickel or manganese; and the thickness of each cobaltosic oxide ultrathin nanosheet doped with the metal is 1.22 nm, nanosheets are in a three-dimensional porous structure, and the nano-pore diameter is 3-6 nm. The ultrathin nanosheet array electro-catalytic material with the nano-porous structure and oxygen vacancies has the following advantages: the material can effectively reduce the overpotential and the spike potential of an oxygen evolution reaction, increase the conversion rate of a single cobalt atom and work continuously and stably in an alkali environment; the steps of a preparation method of the material are simple, the operation is convenient, the cost is low, and the material is environmental-friendly; and new ideas and strategies are provided for the function-oriented design and the performance optimization of an oxygen evolution catalyst of a water electrolysis system.

The invention provides a preparation method of an alloy catalyst for degrading formaldehyde. The method comprises the following steps: (1) adding a TiO2 nano material and a cerium compound into water,carrying out impregnation and stirring to disperse cerium onto the TiO2 nano material, carrying out drying, grinding and roasting to obtain a Ce/TiO2 solid material; (2) adding the Ce/TiO2 solid material into water, carrying out stirring until the Ce/TiO2 solid material is completely dispersed, adding a platinum compound, and carrying out impregnation and stirring to disperse platinum onto the Ce/TiO2 solid material; (3) adding an alkali solution as a stabilizer, uniformly carrying out stirring and mixing, then adding a reducing agent, and carrying out a reduction reaction; and (4) separatingthe solid obtained in the step (3), carrying out water washing, alcohol washing, drying and cooling, and then carrying out grinding to obtain the Pt-Ce/TiO2 catalyst. The method is simple and feasible, and no harsh reaction conditions are required. According to the prepared Pt-Ce/TiO2 catalyst, the Pt nano particles are stabilized through the addition of the cerium according to the method, so that the dispersity is improved, the nano particle size is reduced, abundant oxygen vacancies are provided, and formaldehyde can be effectively decomposed.

The invention provides a zirconia ceramic bone implant and a preparation method thereof. The preparation method comprises the following steps of: mixing and grinding zirconia powder, a stabilizer A, acidic silica sol and aluminum sol to obtain slurry; adding a solvent to the slurry, and carrying out mixing and spray drying to obtain microparticles; placing the microparticles in a mold, carrying out cold forming under 150 to 500 MPa so as to obtain a green body; pre-firing the green body at 700 to 1200 DEG C so as to obtain a biscuit; putting the biscuit in a microwave sintering furnace at 900to 1500 DEG C for 0.2 to 2h so as to obtain zirconia ceramic; and processing the zirconia ceramic to obtain the zirconia ceramic bone implant. According to the preparation method, ways of combining Y/Yb doping, pre-firing and microwave sintering, and in-situ generating mullite by silica sol and aluminum sol are adopted, and a few mullite crystalline grains are prepared to be dispersed on a bone implant of a zirconia matrix, so that the crystalline grain size, density, mechanical properties and hydrothermal ageing resistance of the zirconia ceramic bone implant are improved.

The invention relates to a method for preparing a perovskite-type catalytic material. The method includes the following steps: 1, respectively weighing a perovskite metal oxide and a metal nitrate precursor; 2, putting the perovskite metal oxide and the metal nitrate precursor of step 1 and deionized water into a reaction kettle at the same time, wherein the adding amount of the metal nitrate precursor accounts for 1-5% of the weight of the perovskite metal oxide, and 2-10 ml of the deionized water is added for each gram of the perovskite metal oxide; 3, putting the reaction kettle in an ovenat 200-250 DEG C for 3-5 hours of reaction after sealing; 4, after reaction, performing natural cooling, and alternately washing the reactant by ethanol and the deionized water for filtration; 5, drying the reactant at the temperature of 80 DEG C, and calcinating the reactant at the temperature of 600 DEG C for 1-3 hours. The method has the advantages that the perovskite metal oxide catalyst is optimally treated through addition of metal ions; the defects of perovskite metal oxide catalysts prepared by conventional methods are overcome; the specific surface area is increased, and accordingly,methane is efficiently catalyzed and degraded.

The invention discloses a hierarchical-structure MnOx/TiO2 nanofiber catalyst for acetone oxidation and a preparation method of the hierarchical-structure MnOx/TiO2 nanofiber catalyst. The hierarchical-structure MnOx/TiO2 nanofiber catalyst comprises a primary structure and a secondary structure, wherein the primary structure is titanium dioxide nanofiber obtained by virtue of an electrostatic spinning method, and the secondary structure is a manganese oxide nanoneedle obtained by carrying out crystal growth on the primary structure by virtue of a hydrothermal method. According to the preparation method, the MnOx/TiO2 nanofiber catalyst is prepared by virtue of an electrostatic spinning-hydrothermal synthetic method, has relatively large specific surface area and relatively high surface energy, can be applied to catalytic oxidation reaction of VOCs, particularly applied to acetone discharged in industrial exhaust gas and presents good catalytic performance.

The invention discloses a preparation method of a copper oxide catalyst for catalyzing persulfate to degrade pollutants in water, relates to a preparation method of a copper oxide catalyst for catalyzing persulfate to degrade pollutants in water, and aims to solve the problems of low catalytic efficiency and large dosage of metal oxide. In the preparation process, part of bivalent copper atoms are reduced into monovalent copper atoms, and the structure of a copper oxide crystal is kept, so that Cu (I) and Cu (II) sites exposed on the surface of the material efficiently activate persulfate to generate active oxidizing substances, and the purpose of removing pollutants in water through oxidation is achieved. Compared with other metal oxide catalysts, the prepared catalyst material is high in catalytic activity and small in dosage. The method is applied to the technical field of water treatment.

The invention relates to a method for hydrogen production by reforming of hydrogen sulfide and methane. According to the invention, hydrogen sulfide and methane are subjected to contact reaction withthe catalyst La2NiFeO6. The double-perovskite structure composite metal oxide is applied as a catalyst in the reaction of hydrogen production by reforming of hydrogen sulfide and methane. The catalysthas better high temperature thermal stability and higher activity than single oxide (like Al2O3). As the reaction is carried out at a high temperature of 800DEG C-1100DEG C, the composite oxide withthe double-perovskite structure is more suitable the reaction. In addition, the catalyst has high activity in catalyzing the reforming of hydrogen sulfide and methane for hydrogen production.

The invention provides a method for effectively improving the afterglow intensity of Sr<2>MgSi<2>O<7>:<x>Eu<2+>, <y>Dy<3+> phosphor powder and prolonging the afterglow time of the Sr<2>MgSi<2>O<7>:<x>Eu<2+>, <y>Dy<3+> phosphor powder by means of do-doping by the aid of Li<+>. The method has the advantages that Sr<2+> sites can be replaced by the Li<+> to form Li'Sr with monovalent negative charge during Li<+> co-doping, and accordingly oxygen vacancy with positive charge can be correspondingly generated to complement charge difference and can be used as a trap for capturing electrons and holes in excited states; captured electrons and holes can be gradually released for heat energy and can be recombined with one another, and phosphorescence can be released and is long-afterglow; oxygen vacancy can be continuously increased along with Li<+> doping, captured electrons can be continuously increased, and accordingly the long-afterglow time can be effectively prolonged; the Li<+> is used for compensating charge, and accordingly the charge is in compensation balance when bivalent Sr<2+> is replaced by trivalent Dy<3+>; the Li<+> further can be used as a fluxing agent, the crystallinity of crystals can be effectively improved, the particle sizes of the crystals can be increased, accordingly, crystallization can be improved, and the luminescence intensity of the long-afterglow can be ultimately improved.

The invention relates to an oxygen vacancy containing phenol hydrogenation catalyst and a preparation method thereof, and belongs to the technical field of catalysis. According to the catalyst, ZIF-67is adopted as a precursor, a N-doped carbon material (CN) is prepared from ZIF-67 through a high-temperature roasting and acid pickling method, then oxygen vacancy containing titanium dioxide nano islands are introduced through a sol-gel method and subsequent high-temperature roasting, and finally the catalyst is prepared through activated component salt stirring and dipping and H2 reduction. Theoxygen vacancy containing phenol hydrogenation catalyst and the preparation method thereof have the advantages that by mean of the CN material derived from anatase type TiO2 nano island modified ZIF-67, the interaction between a carrier and active components can be effectively enhanced, the number of the surface active component is increased, the electron-rich character is improved, the antioxygenic property of the active components is enhanced, the catalytic performance of cyclohexanone prepared through phenol hydrogenation is remarkably enhanced, the prepared catalyst has good catalytic stability.

The invention relates to a preparation method of a BiOCl hollow microsphere photocatalyst. The preparation method comprises the following steps: slowly adding a chitosan dispersion solution into a bismuth salt solution, and carrying out stirring at a constant temperature of 5-20 DEG C for 10-100 min to allow the formed system to be in a colloidal state; slowly adding a chlorine salt solution intothe system under a stirring condition, and carrying out stirring for 10-100 min at a constant temperature of 5-20 DEG C; then transferring the reaction system into a high-pressure reaction kettle, andcarrying out a homogeneous reaction and centrifugal separation to obtain a product; and washing the product with distilled water, and performing drying overnight to obtain the BiOCl hollow microsphere photocatalyst. The BiOCl photocatalyst with specific crystal form exposure is prepared through a one-step hydrothermal method; the method is simple in process and low in cost; and the prepared BiOClhollow microsphere photocatalyst has good catalytic degradation performance on TC under simulated sunlight and has good application prospects in the field of photocatalytic degradation of antibioticwastewater.

The invention discloses a core-shell catalyst as well as a preparation method and an application thereof. The core is Zn supported mixed metal oxide NdCoO(3-y) with a perovskite structure, y is oxygenvacancy, and the shell is aluminium oxide containing zirconium sulfate solid acid, wherein the weight ratio of Zn supported mixed metal oxide NdCoO(3-y) with the perovskite structure to aluminium oxide containing zirconium sulfate solid acid is 10:1-2:1; based on the weight of aluminium oxide containing zirconium sulfate solid acid as the baseline, the weight content of zirconium sulfate solid acid is 5%-10%; based on the weight of Zn supported mixed metal oxide NdCoO(3-y) with the perovskite structure as the baseline, the content of Zn in terms of oxide is 5wt%-30wt%. With adoption of the catalyst, methane conversion rate can be increased while selectivity of the target product halomethane can be improved, deep oxidation of halomethane is inhibited, and yield of halomethane is increasedobviously.

The invention discloses a LaCeNiO perovskite catalyst with an ultra-wide Ni (111) crystal face as well as a preparation method and application of the LaCeNiO perovskite catalyst. The preparation method comprises the following steps: by taking water as a solvent, citric acid as a chelating agent, La and Ce as carrier metals and metal Ni as an active metal, drying, screening, calcining and reducing by adopting a sol-gel method to obtain the LaCeNiO perovskite catalyst. The LaCeNiO perovskite catalyst is characterized in that the size of Ni particles reaches 10-25 nm, the crystal face of Ni (111) reaches 10 nm, the proportion of oxygen vacancies reaches 20-30%, the specific surface area of the catalyst is 12-38 m < 2 >/g, the average pore size is 5-13 nm, and the total pore volume is 0.03-0.08 cm < 3 >/g. The catalyst is low in Ni loading capacity and simple to prepare, and when the catalyst is applied to a CO2 methanation reaction, the highest CO2 conversion rate can reach 57.4 mmol CO2/mol Ni/s, and the methane selectivity reaches 99.8%. Compared with a conventional commercial Ni/gamma-Al2O3 catalyst, the catalyst has excellent catalyst activity, stability and regeneration performance for dynamic gas supply and high water vapor atmosphere.

The invention discloses a room temperature formaldehyde purification catalyst. Cerium-zirconium composite oxide with a mesoporous structure and titanium-based solid ionic liquid are combined to serveas a composite carrier, PdPt alloy loaded through a photochemical deposition method serves as an active component, the mass fraction of Pt in the catalyst is 0.02 wt%-0.5 wt%, and the mass fraction ofPd in the catalyst is 1 wt%-5 wt%. The catalyst is prepared by the following steps: (1) preparing a mesoporous cerium-zirconium composite oxide; (2) synthesizing an ionic liquid precursor NMMPS; (3)synthesizing the mesoporous cerium-zirconium composite oxide and a titanium-based solid ionic liquid composite carrier; and (4) loading an active component PdPt. According to the preparation method, metal cations and organic cations are doped, noble metal PdPt is loaded by adopting an ultraviolet chemical deposition method, and the prepared catalyst has excellent moisture resistance and stabilityon the premise of keeping relatively high catalytic efficiency.

The invention discloses a gold nanoparticle-loaded cerium dioxide nanosheet material as well as a synthesis method and application of the material. The method comprises the following steps: adding graphene oxide into water, uniformly conducting dispersing, adding cerium nitrate, and conducting stirring to obtain a precursor; adding the precursor into water to obtain a precursor dispersion liquid, and freezing and drying the precursor dispersion liquid with liquid nitrogen to obtain a dried product; raising the temperature and carrying out calcination treatment to obtain a two-dimensional cerium oxide nanosheet; and adding a polyvinyl alcohol solution and a chloroauric acid solution into water, adding a sodium borohydride solution, uniformly conducting mixing to obtain a mixed solution, adding a two-dimensional cerium oxide nanosheet into the mixed solution, conducting stirring and filtering, and taking a precipitate to obtain the gold nanoparticle-loaded cerium dioxide nanosheet material. The synthesized gold nanoparticle-loaded cerium dioxide nanosheet has a large specific surface area and high-concentration Ce<3+>, the concentration of oxygen vacancies on the surface of cerium oxide is improved, and the gold nanoparticle-loaded cerium dioxide nanosheet shows excellent catalytic performance when being used for catalyzing a carbon monoxide oxidation reaction and has a good application prospect.

The invention discloses cerium oxide modified microwave hydrothermal carbon as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) naturallyair-drying manure outdoors until the water content is 35%-45%, removing impurities, carrying out freeze-drying, and sieving and storing the material in a dark place for later use; (2) preparing a Ce(NO3)3.6H2O solution, and adding ammonia water into the Ce(NO3)3.6H2O solution; and (3) adding a guiding agent into the solution, then adding dried manure, and carrying out microwave heating reaction to obtain the cerium oxide modified microwave hydrothermal carbon. Based on the idea of treating waste with waste, livestock and poultry manure is used as a raw material to prepare hydrothermal carbon,the hydrothermal carbon is coupled with CeO2 with rich oxygen vacancies and low oxidation-reduction potential between Ce < 3 + > and Ce < 4 + >, manure and rare earth oxide CeO2 with coordination unsaturated property are used as raw materials, and a microwave hydrothermal method is used for preparing a CeO2/hydrothermal carbon compound additive. Therefore, low-cost in-situ desulfurization in theanaerobic fermentation process is realized, the quality of an anaerobic fermentation product is improved, the corrosion of H2S to facilities and equipment is reduced, and the service life of the equipment is prolonged.

The invention discloses a platinum-based composite catalyst and method for preparing propylene and synthesis gas through propane oxidative dehydrogenation with CO2 in the presence of hydrogen. A carrier of the catalyst is SiO2 or Al2O3, active components are Pt and Sn, a first auxiliary agent is CeO2, and a second auxiliary agent is any one or more of Fe, Co, Ni, Pd, Ru and the like. Based on 100% of the mass of the catalyst, the loading capacity of Pt is 0.1%-1.0%, the loading capacity of Sn is 0.5%-5.0%, the loading capacity of Ce in the first auxiliary agent is 1.0%-5.0%, and the loading capacity of the second auxiliary agent is 0.01%-0.5%. The catalyst is prepared by adopting an impregnation method, and the preparation process is simple, economical and environment-friendly. The catalyst has high propane and carbon dioxide conversion rate and propylene yield for hydrogen dehydrogenation of carbon dioxide and propane oxide, is rich in synthesis gas, and has a good industrial application prospect.

The invention relates to a preparation method of a manganese phosphate coated lithium-rich oxide positive electrode material. The positive electrode material is obtained by preparing Li1.17Ni0.21Co0.08Mn0.54O2 and a manganese phosphate coated Li1.17Ni0.21Co0.08Mn0.54O2 lithium-rich material. The method has the advantages of simple process, easy operation, low energy consumption, and low cost and easy availability of raw materials; and the prepared positive electrode material has excellent electrochemical performance.