15 results about "Polyoxometalate I" patented technology

This invention discloses a polyoxometalate that catalyzes the Knoevenagel reaction, its preparation method, and its applications. The chemical formula of the polyoxometalate that catalyzes the Knoevenagel reaction is: H3[K(H2O)6][K2(H2O) 10 ]2[Cu(en)2(H2O)2][Cu(en)2(Nb6O 19 Cu(en))2·24H2O, where en = ethylenediamine; the polyoxometalate crystals catalyzing the Knoevenagel reaction belong to the triclinic crystal system with space group P-1; the polyoxometalates catalyzing the Knoevenagel reaction prepared in this invention exhibit excellent heterogeneous catalytic performance in the highly efficient Knoevenagel condensation reaction, showing high yield and high stability under isothermal conditions at a 1:1 substrate ratio and over a wide substrate range. The superior catalytic ability of the polyoxometalates catalyzing the Knoevenagel reaction can be attributed to the presence of dense and effective basic sites on the surface of the heteropolycationic chain, and the increased contact frequency between the organic-inorganic hybrid catalyst and the substrate.

The present application belongs to the technical field of tire manufacturing, and particularly relates to an antiskid tire and a preparation method thereof. The antiskid performance of the tire is significantly improved by adding cerium-doped polyoxometalate-based layered compounds and nitrogen-sulfur co-modified zirconium-based MXene layered compounds in the tread compound. The cerium-doped polyoxometalate-based layered compounds are prepared by hydrothermal reaction and calcination treatment using disodium hydrogen phosphate, sodium molybdate, cerium nitrate and hexanediamine as raw materials. The nitrogen-sulfur co-modified zirconium-based MXene layered compounds are prepared by etching, peeling and co-calcination with thiourea after synthesizing ceramics using titanium powder, aluminum powder, zirconium powder and carbon powder as raw materials. When preparing the tire, the rubber is first mixed with carbon black, the two modified compounds and the additives to obtain a masterbatch, then the vulcanization system components are added to obtain a final rubber compound, and finally the finished product is obtained through extrusion, lamination and vulcanization molding. The antiskid tire prepared by the present application has excellent grip on wet and icy road surfaces.

This invention belongs to the field of catalyst technology, specifically relating to a polyoxometalate-anchored cobalt single-atom catalyst, its preparation method, and its application. The invention uses a polyoxometalate as the anchoring substrate and electronic control unit. First, a cobalt-substituted polyoxometalate precursor is prepared via a coordination reaction, then composited with a ZIF-derived conductive carbon substrate, and finally reduced with hydrogen to obtain the target catalyst. This catalyst effectively inhibits cobalt single-atom aggregation, achieving a cobalt single-atom loading of 3.55 wt%. Under alkaline conditions, it exhibits excellent oxygen reduction catalytic activity, stability, and methanol resistance, with a half-wave potential of 0.826 V. When used in a zinc-air battery, it achieves an open-circuit voltage of 1.48 V and a flow rate of 239.6 mW / cm². 2 With maximum power density and excellent cycle stability, it can replace commercial platinum-carbon catalysts.

This application provides an aqueous zinc-ion battery separator, its preparation method, and its application. The separator includes a membrane body and a polyoxometalate present in the membrane body; the membrane body includes nanocellulose and has a cross-linked structure formed by cross-linking nanocellulose through the polyoxometalate. This cross-linked structure exhibits a superionization effect, which can disrupt the hydrogen bond network of water in the electrolyte, thereby weakening the solvation effect of water, significantly increasing the entropy of the electrolyte, inhibiting parasitic reactions and dendrite growth, enhancing the reversibility of zinc ion stripping and deposition, and thus improving the cycle stability of the battery; in addition, the separator with this cross-linked structure has a uniform pore size distribution and good mechanical strength and zinc ion transport performance.

Provided is an Anderson-type polyoxometalate including titanium (Ti) as a heteroatom in the center of the Anderson-type polyoxometalate. A method for preparing an Anderson-type polyoxometalate includes mixing a titanium precursor and a tungsten precursor to prepare a mixture, sealing the mixture in a container and heating to form a hydrothermal synthetic solution, and cooling the hydrothermal synthetic solution and then adding a solute to form an Anderson-type polyoxometalate.

The application discloses a polyoxometalate composite N-doped carbon quantum dot and a preparation method and application thereof, and belongs to the technical field of photocatalytic nanocomposite material preparation methods. The preparation method of the polyoxometalate composite N-doped carbon quantum dot is as follows: mixing a molybdate and water to obtain a molybdate aqueous solution; mixing a transition metal salt, a hydrogen peroxide solution and water to obtain a mixed solution; heating the molybdate aqueous solution to boiling, then adding the mixed solution, and filtering to obtain a polyoxometalate precursor hot solution; mixing and stirring the polyoxometalate precursor hot solution and an N-doped carbon quantum dot aqueous solution, cooling to room temperature, standing, washing and drying the precipitate to obtain the polyoxometalate composite N-doped carbon quantum dot. The polyoxometalate composite N-doped carbon quantum dot prepared by the application has a syngas CO and H2 yield ratio of 1.3:1 and a yield of >40000 mu mol.g ‑1 ·h ‑1 in a photocatalytic carbon dioxide reduction reaction.

The application discloses a porous chromium-based composite denitration catalyst and a preparation method and application thereof, and belongs to the technical field of denitration catalyst preparation. The preparation method of the porous chromium-based composite denitration catalyst is as follows: a chromium salt, an organic ligand and an Anderson-type polyoxometalate are dissolved in water to perform a hydrothermal reaction to obtain a precursor; wherein the Anderson-type polyoxometalate is selected from one or more of (NH4)4[NiMo6O 24 H6]·5H2O, (NH4)3[CoMo6O 24 H6]·7H2O or (NH4)3[FeMo6O 24 H6]·6H2O; and the precursor is calcined, and the porous chromium-based composite denitration catalyst is obtained. Compared with a single MOF porous chromium-based catalyst, the denitration efficiency of the porous chromium-based composite denitration catalyst can be increased by more than 90%. Meanwhile, the preparation method is simple, easy to control, low in requirement on a synthesis device, can save the amount of active components, reduces the production cost of the catalyst in an all-round way, and is suitable for large-scale industrial production.

The application provides a molybdenum-based polyoxometalate-hemin composite nanomaterial and a preparation method and application thereof, and the method comprises the following steps: under room temperature conditions, molybdenum-based polyoxometalate and hemin are mixed by means of manual grinding, and then the obtained mixture is sequentially subjected to centrifugal separation, washing and vacuum drying, so that a solid-phase molybdenum-based polyoxometalate-hemin composite nanomaterial is prepared. 12 The nanocomposite material is synthesized by a simple manual grinding method, and is prepared through the steps of room temperature grinding, centrifugal separation, washing and vacuum drying without the need of complex equipment, high temperature and high pressure or toxic organic solvents. 12 The colorimetric sensor constructed by the nanocomposite material can rapidly and accurately quantitatively detect the AA content in fresh fruits, and has a wide application prospect in the fields of food nutrition analysis, quality control and on-site detection.

The present application belongs to the technical field of oil and gas drilling engineering, and particularly relates to a polymer-coated inhibitor for strong inhibition drilling fluid and a preparation method thereof; the inhibitor is prepared by aqueous solution polymerization of acrylamide, acrylamidomethylpropane sulfonic acid, dimethyldiallylammonium chloride, vinyltrimethoxysilane and two novel inorganic modified compounds. The two inorganic modified compounds are a titanate intercalated magnesium aluminum tin silicate nanocomposite and a polyoxometalate grafted rare earth doped cerium dioxide nanorod, respectively. The former is prepared by coprecipitation and intercalation reaction, and the latter is prepared by hydrothermal synthesis and graft modification. The present application significantly improves the hydration inhibition capacity for shale, and can still maintain stable coating effect in high temperature and high salt environment, effectively solving the problem of wellbore instability. The preparation method is simple in process, the raw materials are all commercially available, and is suitable for industrial production, and has a broad application prospect in the field of water-based drilling fluid.

The application discloses a preparation method of a boronized MoNi self-supporting catalyst loaded on foamed nickel, a catalyst and application; the preparation method comprises the following steps: reacting a nickel source and a molybdenum source in a solvent to obtain an Anderson-type MoNi polyoxometalate precursor; mixing the precursor with a boron source to obtain a mixture of the precursor and boron; uniformly mixing the mixture of the precursor and boron with a NaCl-KCl molten salt medium to obtain a precursor mixture; calcining the precursor mixture and a foamed nickel substrate under an inert atmosphere to make the precursor undergo a boronization reaction and be loaded on the foamed nickel; and washing and drying the calcination product to obtain the catalyst; the Anderson-type precursor is used to realize uniform dispersion of Mo and Ni elements at a molecular scale, the electronic structure is regulated through boronization treatment, the molten salt confined reaction and the foamed nickel self-supporting structure are combined, and therefore the catalyst exhibits excellent bifunctional catalytic activity of oxygen evolution and hydrogen evolution and good stability under alkaline conditions.

The present application relates to the technical field of biodiesel preparation, and particularly discloses a metal-doped vacancy-type polyoxometalate ionic liquid, a preparation method and application thereof. The ionic liquid is composed of sulfonic acid group (-SO3H) containing organic cations derived from 1,3-propane sultone and vacancy-type Keggin structure heteropolyanions (PW 2+ MO 40 ) doped with metals (Zn 3+ , Fe 4+ or Sn 11 ), forming a bifunctional synergistic catalytic system with stable Brønsted acid sites and controllable Lewis acid sites. The catalyst can simultaneously and efficiently catalyze esterification and transesterification, realize the "one-pot" conversion of high-acid-value oil and fat raw materials, significantly improve the biodiesel yield, and due to the unique structure, the active sites are stable and not easy to be lost, and the recycling performance is excellent. The present application provides a new multifunctional catalyst for green and efficient production of biodiesel, and has important industrial application prospect.

This invention relates to the field of catalysis, specifically to a metal-organic framework (MOF), its preparation method, and a method for hydrolyzing 2,5-dimethylfuran. The MOF comprises a polyoxometalate component, the contact angle between the MOF and water is greater than 80°, and the total acidity is 150-700 μmol·g. ‑1 The metal-organic framework provided by this invention contains polyoxometalate components and has a contact angle with water of more than 80°. It also exhibits a polyhedral morphology with an arbitrary edge length of not less than 3 μm. This characteristic gives the metal-organic framework unique acidic and hydrophobic properties, as well as excellent hydrolytic activity.

The application discloses a preparation method and application of a copper selenide polyoxometalate nanocluster, relates to the technical field of biological nanomaterials, and comprises the following steps: dissolving ammonium molybdate tetrahydrate in ultrapure water to obtain an ammonium molybdate solution, dissolving copper chloride dihydrate in ultrapure water to obtain a CuCl2 solution, mixing the ammonium molybdate solution and the CuCl2 solution to obtain a mixed solution, dropwise adding an ascorbic acid solution into the mixed solution obtained in the previous step, continuing to stir and react after the dropwise adding is completed, loading the obtained Cu-POM crude solution into a dialysis bag, performing freeze-drying treatment on the Cu-POM solution after dialysis is completed, obtaining a Cu-POM powder product, preparing a Cu-POM solution with a concentration of 0.8-1.2 mg / mL and mixing the solution with a solution at a volume ratio of 1:1, loading the obtained Cu-Se-POM crude solution into a dialysis bag after the reaction is completed, and performing freeze-drying treatment on the Cu-Se-POM solution after dialysis is completed, to obtain a Cu-Se-POM powder product. Compared with a preparation method of a traditional polyoxometalate doped material, the preparation efficiency is high, the raw material cost is low, and the preparation method is environment-friendly.

The present application relates to the technical field of water evaporator, in particular to a method for preparing a photo-thermal water evaporator based on conjugated ligand ZnMo multi-nuclear cluster photo-thermal material. Under the condition of hydrothermal method, zinc citrate dihydrate, molybdic acid and pyridine / 2,2-bipyridine / 1,10-phenanthroline are introduced into the experimental process as a raw material, through washing, high temperature annealing reaction, cooling to room temperature, the conjugated ligand ZnMo multi-nuclear cluster photo-thermal material powder is obtained, which is blended with polyvinylidene fluoride, and through vacuum filtration and drying, the DMF solvent in the mixed solution is extracted, the polyoxometalate and PVDF are uniformly attached to the surface of the nylon film, the obtained filtrate is dried in a room temperature environment, then the film slice is prepared, and the photo-thermal water evaporator is prepared. The photo-thermal water evaporator prepared by this method not only has excellent performance and high stability, but also has excellent water evaporation capacity, and shows great potential in the field of seawater desalination.