67results about How to "Suppress stacking" patented technology

The invention discloses a composite nanostructure based on a three-dimensional porous transition metal carbide Ti3C2MXene and a general preparation method thereof, and belongs to the field of nanomaterials. The three-dimensional composite structure is composed of a three-dimensional porous Mxene-supported inorganic nanostructure, and has a honeycomb hierarchical porous structure. A precursor of atwo-dimensional transition metal carbide and a metal-organic framework compound is subjected to high-temperature pyrolysis or a chemical reaction in an inert or reactive atmosphere to prepare the composite nanostructure with a controllable size. According to the composite nanostructure, stacking of MXene itself is inhibited, an active surface area, porosity, and ion permeability of MXene are increased, and thereby a surface interface of MXene is efficiently used. At the same time, introduction of the metal-organic framework compound realizes uniform and stable compounding of the three-dimensional porous MXene and an inorganic nanomaterial, the fundamental difficult problem that plagues exerting and application of inorganic nanomaterial performance is solved, and the composite nanostructurehas wide application prospects in the fields such as catalysis, energy, photo-electricity, space technology, and military industry.

The invention provides a preparation method of ultrathin graphite phase carbon nitride. The preparation method comprises steps as follows: melamine is calcined firstly, and blocky g-C3N4 is obtained; blocky g-C3N4 is uniformly dispersed in deionized water and subjected to ultrasonication; a product obtained after ultrasonication is subjected to centrifugal separation, and solids are collected and dried; finally, a dried product is calcined again, and a target product is obtained. According to the preparation method of ultrathin graphite phase carbon nitride, mass preparation and thickness regulation of ultrathin g-C3N4 with the thickness of 0.8-1.2 nm equal to the thickness of 3-4 atom layers are realized, no organic solvent or toxic chemical reagent participates in a reaction process, so that the problems of structure defects and environmental pollution which are caused by introduction of impurities can be effectively solved, and on the basis of the non-toxic characteristic of prepared g-C3N4, the preparation method can be widely applied to photocatalysis, electro-catalysis, biosensing, bioimaging and spintronics. The whole preparation process is simple to operate, high in controllability, good in repeatability, green, environment-friendly and suitable for large-scale production.

The invention discloses a method for preparing functionalized graphene through Mannich reaction. The method comprises the following steps of: reducing oxidized graphene by taking plant polyphenols and derivatives of the plant polyphenols as reducing agents to obtain the polyphenol modified graphene; and then preparing the functional graphene with amphipathy through Mannich reaction between polyphenol groups on the surface of the graphene and polyether amine. The method disclosed by the method has the advantages of mild preparation conditions, simple and efficient purification process and no-purification of intermediate products. Simultaneously, raw materials for preparation of the functionalized graphene comprise the reducing agents and a modifier and have the characteristics of rich sources and low cost, and therefore, the functionalized graphene and colloids thereof can be efficiently prepared on a large scale. The functionalized graphene can be used for directly preparing a graphene hybrid material with excellent electric conductivity and toughness, has very good solvent dispersivity and excellent storage stability, and is suitable for compounding with various polymers to prepare a polymer/graphene composite material with high performance.

The invention discloses a composite lithium metal negative electrode based on an MXene aerogel and a synthesis method thereof, which belong to the field of lithium batteries. The composite lithium metal negative electrode comprises metal lithium and the MXene aerogel, wherein the MXene aerogel is assembled by cross-linking of two-dimensional MXene sheets and has a three-dimensional hierarchical porous structure; the MXene aerogel pores are filled with the metal lithium; and the thickness of the MXene aerogel is 300 mum to 800 mum. According to the composite lithium metal negative electrode prepared in the invention, rich pro-lithium functional groups on the surface of the MXene aerogel can be specifically combined with the lithium ions, uniform nucleation of lithium is thus realized, formation of lithium dendrites is suppressed, and the coulombic efficiency, the safety and the cycle life of the lithium metal negative electrode are effectively improved.

The invention relates to a graphene/MXene composite fiber flexible electrode material based on a solid electrolyte and a preparation method of a knittable supercapacitor. High-performance graphene oxide and MXene nanosheets are prepared through an improved Hummers method and an etching method, a macroscopic graphene/MXene composite fiber electrode material is prepared through wet spinning by meansof the liquid crystal self-assembly behavior of the graphene oxide and the MXene nanosheets, and the macroscopic graphene/MXene composite fiber electrode material is assembled into the supercapacitor. The preparation method is simple in process and low in equipment requirement, and the prepared flexible knittable supercapacitor is good in biocompatibility, has excellent electrochemical performance and good flexibility and stretchability, and can be widely applied to the fields of portable and wearable electronic equipment and the like.

The invention discloses preparation and application of a graphene composite fiber nonwoven fabric for catalytically degrading neuropathic chemical warfare agents, and belongs to the field of chemicalprevention. MOFs (Metal Organic Frameworks) nanoparticles are synthesized on the surface of fibers by a solvothermal method by using graphene fibers as carriers, wherein the diameter of the graphene fibers is 20 to 100 [mu]m; an MOFs catalyst is UiO-66-NH2; the particle dimension is 50 to 400 nm; and the composite fiber nonwoven fabric is graphene@UiO-66-NH2, and the thickness is 50 to 300 [mu]m.The graphene composite fiber nonwoven fabric is prepared through wet spinning and subsequent vacuum suction filtration, and has an efficient photothermal conversion effect. Under the condition of simulated sunlight, the catalytic degradation half-life period of the graphene@UiO-66-NH2 on an optimum analog of methyl paraoxon of a nerve poison of GD is 1.6 min; complete degradation can be almost realized within 20 min; and excellent capability of fast and catalytically degrading the neuropathic chemical warfare agents is shown.

The invention discloses MXene/graphene/carbon nanotube gel with high magnification and long service life as well as a preparation method and application of the MXene/graphene/carbon nanotube gel. The invention belongs to the field of supercapacitor electrode materials and preparation thereof. The invention aims to solve the technical problem that the existing supercapacitor electrode material MXene is easy to oxidize, stack and agglomerate. The MXene/graphene/carbon nanotube gel provided by the invention is formed by mutual crosslinking of a two-dimensional MXene sheet layer, a graphene nanosheet and a carbon nanotube, and the MXene/graphene/carbon nanotube gel has a three-dimensional hierarchical porous structure. The three-dimensional porous open structure effectively inhibits serious stacking and agglomeration of two-dimensional MXene sheet layers, improves the surface utilization rate of the MXene material, increases the number of active sites, and increases the specific capacity of the material; meanwhile, due to the addition of graphene and vitamin C, the oxidation of MXene can be inhibited, so that the gel has relatively good oxidation resistance; in addition, the porous structure can be used as a reservoir to shorten the diffusion path of electrolyte ions and improve the rate characteristic of the electrode.

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 discloses an aperture-controllable honeycomb three-dimensional porous MXene and a general synthesis method thereof, and belongs to the field of nano materials. According to the method, two-dimensional transition metal carbide MXene and a corresponding polymer template are used as precursors, and the honeycomb three-dimensional porous transition metal carbide with the controllable internal pore size is prepared through a spray pyrolysis technology. The honeycomb three-dimensional porous transition metal carbide prepared by the method is of a hierarchical porous three-dimensional structure formed by three-dimensional tight crosslinking of the two-dimensional MXene, the pore size is 260-800 nm, the pyrolysis time is extremely short, and the honeycomb three-dimensional porous transition metal carbide has excellent conductivity and has the specific surface area and pore volume far exceeding those of the two-dimensional MXene; the porosity and the ion permeability are greatly improved, so that an MXene surface interface is efficiently utilized, the application and processing properties of the MXene surface interface are improved, and the disclosed MXene has a wide application prospect in the fields of catalysis, energy, photoelectricity, space technology, war industry and the like.

The invention discloses a modification method of an easily-to-grab anti-skid swim ring. The modification method comprises the following steps: mixing graphene oxide and modified molybdenum disulfide,adding deionized water, sealing, carrying out ultrasonic stirring, adding ammonia water to adjust the pH value to be neutral, adding waterborne polyurethane, and uniformly mixing to obtain pretreatedwaterborne polyurethane; adding modified nano calcium carbonate and modified silicon dioxide into the obtained pretreated waterborne polyurethane, heating and magnetically stirring, adding plasticizerglycerol, continuously stirring, standing and degassing to obtain an antiskid wear-resistant coating; and uniformly coating the surface of a swim ring with the obtained antiskid wear-resistant coating by using a coating rod, naturally drying, and carrying out rewetting treatment in a constant-temperature and constant-humidity box to obtain the antiskid wear-resistant swim ring.

The invention provides a hollow LDH/MnO2 nanocage composite material as well as a preparation method and application thereof, and the preparation method comprises the following steps: by taking ZIF-67as a self-template, forming a hollow LDH nanocage in situ by adopting simple etching and hydrothermal reaction, and growing ultrathin MnO2 nanosheets on the hollow LDH nanocage to obtain the LDH/MnO2nanocage composite material with a hollow dodecahedron structure. The preparation method disclosed by the invention is simple and easy to control in preparation process, environment-friendly and suitable for large-scale industrial production. The hollow structure and synergistic effect of the composite material can fully expose active sites and accelerate the mass transfer process, and when the composite material is used as a positive electrode material for a lithium-air battery, the reaction kinetics can be accelerated, the charging overpotential can be reduced, and the cycling stability ofthe battery can be improved.

The invention discloses a preparation method of functionalized graphene oxide. The method includes: under an ice-water bath condition, adding cyanuric chloride into a mixed solution of acetone and water, stirring the substances evenly, adding ammonia water, carrying out reaction at 1-5DEG C for 30-50min, and then conducting filtering, washing and drying to obtain a material A; adding the materialA into 1, 4-dioxane, mixing the substances evenly, adding a 1, 4-dioxane solution of p-aminodiphenyl amine and sodium carbonate, conducting stirring at room temperature for 30-100min, and performing filtering, washing and drying to obtain a material B; adding the material B into 1, 4-dioxane, adding 1H, 1H-perfluorooctylamine, adjusting the pH to 7, carrying out reaction at 80-90DEG C for 3-4h, and conducting standing, filtering and drying to obtain a material C; subjecting graphene oxide to acylating chlorination, then adding the product into dimethylformamide, adding a material C, carrying out reaction at 80-90DEG C for 20-30h, conducting filtering and drying, mixing the obtained material with plant polyphenol and water evenly, carrying out reaction at 35-60DEG C for 30-48h, and performing drying.

The invention provides a phosphine-containing fused heterocyclic compound as well as a preparation method and an application thereof. The phosphine-containing fused heterocyclic compound has a structure as shown in a formula I, a formula II, a formula III, a formula IV or a formula V. The phosphine-containing fused heterocyclic compound provided by the invention has double phosphorus-oxygen bonds,and an electron-withdrawing or large-volume Ar3 group and an Ar4 group are introduced; therefore, the material has a low LUMO energy level, a high electron transport capability and a high thermal decomposition temperature, can be used as an electron transport material of a photoelectric device, reduces the driving voltage of the device, improves the current efficiency, maintains thermal stabilityin the preparation and use processes of the device, and prolongs the service life of the device.

The invention discloses a silicon dioxide-based metal sulfide composite material prepared by a two-step hydrothermal method, concretely, growing a nano flower-like structure of manganese disulfide andcobalt disulfide on the outer surface of template agent silicon dioxide by adopting a two-step hydrothermal method, and etching the silicon dioxide by hydroxyl through vulcanization reaction. Thus, part of silicon dioxide is released from hydrolysis of sulfide ions, a certain hole is etched in an internal silicon dioxide template, ion migration is facilitated, and the layered nano metal sulfide composite material based on silicon dioxide can be prepared. The preparation method comprises the following steps: 1, preparing a composite metal oxide precursor; and 2, preparing the silicon dioxide-based metal sulfide composite material. When the material is used as a supercapacitor electrode material, the material is charged/discharged within the range of 0-0.55 V, and when the discharge currentdensity is 1 A/g, the specific capacitance is 1150-1160 F/g. The material has excellent material stability and excellent ion transmission capability.

The invention provides a corona-resistant polyimide based composite material and a preparation method thereof. The preparation method provided by the invention comprises the steps that an anionic two-dimensional layered material and an organic intercalation agent are subjected to heating reaction in a solvent; then, the mixture and polyimide polymerization monomers are subjected to in-situ polymerization reaction in the solvent; a mixed solution I is obtained; inorganic nanoparticles and the polyimide polymerization monomers are subjected to in-situ polymerization reaction in the solvent; a mixed solution II is obtained; then, the solution I and the solution II are mixed; heat treatment is performed to obtain the polyimide based composite material. The composite material prepared by the preparation method provided by the invention can improve the polyimide corona-resistant performance and also obtains higher mechanical property and excellent temperature resistant performance.