154results about How to "Realize large-scale preparation" patented technology

The invention relates to a method for preparing graphene powder in large scale, which is characterized by comprising the following steps of: firstly, uniformly peeling graphene oxide into a graphene oxide suspension solution; then, atomizing the graphene oxide solution by using the spray drying technology comprising spray pyrolysis drying and spray freeze drying, and removing a solvent to obtain graphene oxide powder; and finally, oxidizing grapheme by using the non-expansion heat treatment process to obtain non-agglomerative graphene powder. The continuous preparation process of the spray technology and the non-expansion heat treatment process ensure the large-scale preparation of the graphene powder. The prepared graphene powder comprising intermediate product graphene oxide powder does not have agglomeration and has good dispersivity in the solvent. The graphene powder is used as a filling material to prepare high strength composite materials, conductive composite materials, novel air-tight flame-retardant composite materials, novel nanodevices and the like.

The invention discloses a large-scale preparation method of a transparent super-hydrophobic / super-amphiphobic coating. The method comprises the steps of ultrasonically dispersing nano particles into an alcohol-water mixed system and carrying out hydrolysis and condensation reaction on the nano particles and fluoride-free or fluorine-containing organosilane under the acid or alkali catalysis action to prepare a transparent suspension liquid of a fluoride-free or fluorine-containing organosilane polymer-nano particle compound; and applying the transparent suspension liquid of the compound on the surface of a substrate material through spraying or dip-coating to obtain the transparent super-hydrophobic / super-amphiphobic coating with good performance. Preparation of the transparent super-hydrophobic / super-amphiphobic coating of 10-100m<2> can be completed within an hour; large-scale preparation of the large-area transparent super-hydrophobic / super-amphiphobic coating is achieved for the first time; the preparation method is low in cost and simple in process; and the prepared coating has excellent super-hydrophobic or super-amphiphobic property, relatively good mechanical stability, chemical stability and environment stability, and has a wide application prospect.

The invention discloses a jet yarn spinning device for an electrostatic spun nano fiber, which includes a collecting device, wherein two thread jetting devices are arranged on the two sides of the collecting device and connected with a high-voltage electrostatic generator; a buncher is arranged below the collecting device; the two thread jetting devices are arranged between the collecting device and the buncher and symmetrically and oppositely arranged along the axis; a jet nozzle twister is arranged below the buncher; a delivery roller is arranged below the jet nozzle twister; a winding mechanism is arranged below the delivery roller; and the collecting device, the buncher, the jet nozzle twister and the delivery roller are arranged along the same axis from top to bottom. The electrostatic spun nano fiber spinning device integrates thread jetting, collecting, drawing, twisting and winding, and can continuously prepare the electrostatic spun nano fiber yarns. The nano fiber spinning method has simple process, high yarn yield, is suitable for multiple polymer yarn solutions, and realizes the continuous and scaled preparation of the nano fiber yarns.

The invention relates to a surface-enhanced Raman scattering (SERS) active substrate based on star-shaped gold nanoparticles and a preparation method thereof, wherein the SERS active substrate is good in enhancement effect, low in cost, simple and convenient in preparation method and good in repeatability. By dipping an ammonified glass sheet into a star-shaped gold nanoparticle solution, the highly uniform SERS active substrate is obtained through the function of static adsorption under the effect of magnetically agitating at a low speed. According to the invention, the star-shaped gold nanoparticles are combined with a static self-assembly method, excellent SERS effect of the star-shaped gold nanoparticles is used for making up main deficiency in preparation of the SERS substrate by using the static self-assembly method, therefore, the high-efficiency SERS active substrate which is simple in preparation method and good in both repeatability and enhancement effect is formed.

The invention discloses a preparation method of a black phosphorus alkene-graphene composite material hollow microsphere. The preparation method comprises the steps of adding a black phosphorus alkene nanosheet or black phosphorus alkene quantum dot dispersion liquid into oxidized graphene nanosheet dispersion liquid firstly, and mixing the black phosphorus alkene and the oxidized graphene by adopting a mechanical agitation method; spraying the mixed dispersion liquid of the black phosphorus and the oxidized graphene into liquid helium by a spraying method and rapidly freezing the mixed dispersion liquid into microballoons; then putting the obtained black phosphorus alkene and oxidized graphene composite material microballoons into a freezer dryer for freeze-drying, so as to obtain the black phosphorus alkene and oxidized graphene composite material hollow microballoons; reducing the oxidized graphene into graphene at high temperature under the protection of nitrogen or argon, so as to obtain the balck phosphorus alkene and graphene composite material hollow miroballoons at last. The prepared black phosphorus alkene and graphene composite material hollow miroballoons have a potential application prospect in the fields such as lithium ion batteries, supercapacitors, sensors and filtration purification.

The invention discloses preparation for compound hollow sphere CdS-TiO* and application in photocatalytic hydrogen production by water decomposition. The preparation method uses inexpensive cadmium source and titanium source, adopts a hydrothermal method, a two-step impregnation method and a sol-gel method for preparing compound hollow sphere CdS-TiO* nanophase materials; and the technical process is simple and practicable and can realize scale production. CdS and TiO2 are compounded, which broadens the spectral response range of TiO2; the prepared compound hollow sphere CdS-TiO is used as photocatalyst for solar energy visible light catalyzing hydrogen production by water decomposition; compared with the TiO2 photocatalyst, the optical energy utilization ratio of the solar energy is substantially increased and the speed of hydrogen production is obviously increased.

The invention discloses a dispersion method for carbon nanotubes, belonging to the field of new materials. The method comprises the following steps: (1) mixing the carbon nanotubes with a binder; (2) pressing the obtained mixture so as to prepare an electrode; (3) connecting the electrode with a negative electrode of a direct-current power supply, and using materials like metal as a positive electrode of the power supply; (4) keeping a certain distance between the positive electrode and the negative electrode of the power supply; and (5) turning on the power supply so as to generate electro-induced heat sources like electric arcs, plasmas and electric sparks with a certain strength between the two electrodes of an electric circuit, and subjecting the binder absorbed by the carbon nanotubes to phase change under the action of high temperature so as to effectively disperse the carbon nanotubes. The invention has the following beneficial effects: the dispersion method for the carbon nanotubes provided by the invention has obvious dispersion effect and is easy to realize large-scale preparation.

The invention relates to a preparation technology for graphene transparent conductive films, in particular to a large-scale preparation method for stably-doped large-area graphene transparent conductive films. According to the method, the doping effect and stability of the graphene transparent conductive films are improved through a sandwich structure, and a doping agent is in direct contact with the intrinsic surface of graphene and positioned between the graphene and a transparent substrate. The method comprises the following steps: firstly, forming the doping agent on the surface of the graphene or the transparent substrate on an initial substrate; secondly, combining the graphene, the doping agent and the transparent substrate; finally, separating the graphene from the initial substrate so as to prepare the stably-doped large-area graphene transparent conductive films. The graphene serves as an outer-layer protection film of the doping agent, so that the doping stability can be improved; the intrinsic surface of the graphene is in direct contact with the doping agent, so that the pollution of an interface between the graphene and the doping agent by impurities can be avoided, the doping effect of the doping agent can be improved, and the conductivity of the film can be enhanced; the transferring and doping processes of the graphene are combined, so that the large-scale preparation can be easily realized.

The invention discloses an all-solid-state battery with low interface resistance and a preparation method of the all-solid-state battery, the all-solid-state battery comprises an integrated battery cell, and the integrated battery cell comprises a positive electrode current collector layer, a positive electrode layer, a buffer layer, an organic-inorganic composite electrolyte membrane, a negativeelectrode layer and a negative electrode current collector layer which are arranged in sequence; the organic-inorganic composite electrolyte membrane comprises a high-molecular polymer matrix, a lithium salt and an inorganic filler, the high-molecular polymer matrix is selected from polyvinylidene fluoride or a polyvinylidene fluoride-hexafluoropropylene copolymer; the lithium salt is selected from at least one of LiTFSI, LiFSI, LiClO4, LiPF6, LiBF4, LiBOB, LiDFOB and LiPF2O2. According to the invention, a layer of soft contact is formed between hard interfaces of the positive electrode and the negative electrode, multiple layers of films are integrally formed, different component film structures are seamlessly interconnected, and the interface problem of the solid-state battery is effectively improved. The solid-state battery provided by the invention has excellent capacity exertion and cycling stability, and the preparation method is high in efficiency and low in cost.

The invention discloses preparation for p-n junction hollow sphere TiO-CdS nanophase compound material and application in photocatalytic hydrogen production by water decomposition; the method uses inexpensive cadmium source and nickel source, adopts a hydrothermal method, a synthesis method, and a four-step impregnation method for compounding an n-NiO semiconductor and a p-CdS semidconductor to prepare the p-n junction hollow sphere TiO-CdS nanophase compound material; and the technical process is simple and practicable and can realize scale production. The p-n junction hollow sphere TiO-CdS nanophase compound material is used as photocatalyst for solar energy visible light catalyzing hydrogen production by water decomposition, speeds up the conveying rate of photo-generated electrons and substantially increases yield of the hydrogen production.

The invention discloses a method for preparing a novel Fe3+-doped TiO2 opened-port or closed-port hollow sphere composite catalyst, which comprises the following steps of: preparing a Fe3+-doped carbon / titanium dioxide nuclear shell particle by using a template method-hydrolysis cladding method and calcining for 2-4h at certain temperature to obtain the Fe3+-doped TiO2 opened-port or closed-port hollow sphere composite catalyst. The method can be applied to solar visible light catalytic degradation cation blue dye solution. In the invention, the Fe3+-doped TiO2 composite hollow sphere is prepared from ferric sources, titanium sources and carbon spheres with low cost, thereby the invention has the advantages of no pollution caused by used raw materials, simple process of method, no pollutant emission in the preparation process, short preparation period, less energy consumption and low cost, and can realize scale preparation, and the invention belongs to the green synthesis technology. A light absorption side of the composite light catalyst carries out red shift to a visible light region after the doping of Fe3+, so that the utilization ratio of the solar visible light is improved and the degradation efficiency under the visible light is greatly improved.

The invention discloses an ultra-thin two-dimensional layered material nanosheet and a preparing method thereof. The nanosheet has a single layer or few layers and has the nanometer thickness of 0.8-2.5 nm and the size of 0.5-10 micron. The preparing method of the nanosheet specifically includes the following steps of firstly, putting high-purity two-dimensional layered material initial powder ina centrifugal tube, injecting liquid gas into the centrifugal tube, and putting the opened centrifugal tube in a thermal insulation barrel containing the liquid gas for thermal insulation for 0.5-6 hours; secondly, taking out the centrifugal tube, instantly dispersing the powder in a solvent after the liquid gas completely volatiles, and conducting ultrasonic treatment for 0.5-4 hours at the ultrasonic powder of 120-300 W to prepare the ultra-thin two-dimensional layered material nanosheet. The nanosheet is simple in process and low in cost, the high-efficiency preparation of the typical two-dimensional layered material nanosheet of graphene, molybdenum disulfide, boron hexahydrate and the like can be achieved.

The invention belongs to the technical field of pharmaceutical chemistry, and discloses a semaglutide purifying method. The purifying method comprises the following steps: taking a semaglutide sample to be purified, allowing the sample to go through a chemically bonded silica gel chromatographic column in order to carry out primary separation, carrying out gradient elution with an A1 solution and B solution mixed solution, and collecting an elution component to obtain a primary purification product; allowing the primary purification product to go through a chemically bonded silica gel chromatographic column in order to carry out secondary separation, carrying out gradient elution with an A2 solution and B solution mixed solution, and collecting an elution component to obtain a semaglutide solution, wherein the above A1 solution is a carbonate solution; the above A2 solution is a phosphate solution; and the B solution is an acetonitrile and isopropanol mixed solution with a volume ratio of acetonitrile to isopropanol of (8:2)-(9:1). The purifying method has the advantages of realization of high purity of the prepared semaglutide, substantial improvement of the semaglutide yield, simple operation, and facilitation of realization of large-scale preparation of semaglutide.

The invention discloses a method for large-scale preparation of a transition metal oxide porous microsphere, and belongs to the technical field of synthesis of nano materials. The key points of the technical scheme of the invention are as below: dissolving polyhydric alcohol in an organic solvent under room temperature to form a uniform solution; adding the transition metal salt to the uniform solution under the condition of stirring, and uniformly mixing to obtain a precursor solution; transferring the precursor solution for drying in a spray dryer, and collecting the powder at the bottom of a drying tower by a cyclone separator; placing the powder in a muffle furnace, heating to 350-650 DEG C at heating rate of 1-8 DEG C / min, calcining 0.5-5 h and naturally cooling to room temperature obtain the transition metal oxide porous microsphere. The invention realizes the large-scale preparation of transition metal oxide porous microsphere; spray drying can realize continuous process in nanomaterial preparation; and the prepared transition metal oxide porous microsphere can be used directly, without crushing or grinding.

The invention discloses preparation of a novel red soil-base polymer catalyst and an application of the catalyst in preparation of hydrogen energy through photo-catalytic water splitting. According to the preparation method, industrial solid wastes of red mud at different places of production are used as the raw materials respectively to prepare the red soil-base polymer catalyst under the excitation of a chemical activator. The preparation of the red soil-base polymer catalyst has the advantages that the red mud raw material can be fully utilized and no three wastes are emitted; the red soil-base polymer catalyst is applied to preparation of hydrogen energy reaction through the photo-catalytic water splitting, can be used repeatedly and causes no secondary pollution. The preparation of the red mud-base polymer catalyst and the hydrogen production reaction process are simple and large-scale production and application can be realized.

The invention provides a new production process for large-scale synthesis of long-chain RNA drugs. The process is characterized by specifically including the steps of: DNA transcription template design; template preparation and purification; in-vitro transcription; and product purification, purity detection and the like. The production process provided by the invention is especially suitable for synthesis of long-chain RNA drugs with a stable secondary structure. With the characteristics of simple operation and low cost, the process provided by the invention meets the requirements of large-scale production, and the produced long-chain RNA drugs can be used for cell experiments, animal experiments and other preclinical RNA drugs' functional study.

The invention relates to a graphene band prepared with an acid oxidized flat carbon nano-tube and a method for preparing the graphene band. The method includes the specific and main steps: preliminarily oxidizing a carbon nano-tube with acid; oxidizing the carbon nano-tube with strong oxidizers; adding water for hydrolysis; adding hydrogen peroxide for purification; and preparing the graphene band after washing and drying. The acid oxidized flat carbon nano-tube is precisely, directionally and longitudinally cut along the edge of the acid oxidized flat carbon nano-tube, so that the regular and uniform high-quality graphene band is prepared. The method is simple and convenient, is easy to implement and control, and can be used for directional cutting in a wide temperature range and under various oxidization conditions, and preparing the graphene band on a large scale. The prepared graphene band is uniform, regular and narrow, has uniform layers and neat edges, and can be applied to composite materials, conductive and heat conducting materials, sensors, electronic circuits, micro-nano devices and related fields.

The invention provides a graphene flame-retardant elastic composite. The composite is characterized by being prepared from, by mass, 0.5-10% of graphene microchips, 20-35% of fire retardant, 10-30% ofthermoplastic elastomer, 30-60% of solvent and 0.1-1.5% of auxiliaries. In addition, the invention further provides a composite film containing the graphene flame-retardant elastic composite and a preparing method of the composite film. The composite obtained with the thermoplastic elastomer, the fire retardant and the solvent with different elasticity moduli as the film forming materials and thegraphene microchips as the conductive filler has the advantages of flame retardance, high conductivity, bendability, high adhesiveness and the like, and therefore the composite film prepared from thecomposite also has the advantages of flame retardance, high conductivity, bendability, high adhesiveness and the like, and the composite film can be applied in the fields of electromagnetic shielding, far infrared electric heating products, flexible conductive electrodes and the like, is wide in application range, and effectively overcome the problems that an existing electric heating film product is poor in bending resistance and potential safety hazards such as spontaneous combustion are caused by local overheating.

The invention discloses a preparation method of a Sr<2+>-doped TiO2 composite hollow sphere photocatalyst, and belongs to the environmental protection field. The method comprises the following steps: adopting a template method-hydrolysis coating method to prepare a Sr<2+>-doped C / TiO2 core-shell particle, and calcining the particle at a certain temperature for a certain time to obtain the Sr<2+>-doped TiO2 composite hollow sphere photocatalyst. The Sr<2+>-doped TiO2 composite hollow sphere photocatalyst prepared in the invention can be used in the visible photocatalysis degradation of a cationic dye solution. The method has the advantages of pollution-free raw materials, simple technology, no emission of pollutants in the preparation process, short preparation period, less energy consumption and low cost, is a green synthesis technology, and can realize the large scale preparation. The doping of Sr<2+> improves the visible response of the photocatalyst, improves the lives of electrons and cavities, promotes the transmission of photoelectrons and substantially improves the visible photocatalytic activity of the catalyst.

The invention discloses a preparation method of a Fe and N-doped porous carbon nanofiber applicable to a cathode catalyst for a polymer fuel cell. The preparation method comprises the following concrete steps: mixing a carbon nanofiber with pyrrole in proportion, adding a certain amount of a ferric iron ion solution, polymerizing the pyrrole, uniformly coating the surface of the carbon nanofiber with the polymerized pyrrole, removing unreacted impurities, performing suction filtration, naturally drying, soaking the carbon nanofiber coated with the polymerized pyrrole in the iron ion solution, absorbing ferric iron ions until the saturation rate is reached, then, performing suction filtration and drying, and performing high-temperature treatment, acid reflux and high-temperature treatment to obtain an efficient Fe and N-doped porous carbon nanofiber electrocatalyst. The Fe and N-doped porous carbon nanofiber is prepared from the carbon nanofiber, pyrrole and iron ions as precursors; raw materials are low in price and easily available; the Fe and N-doped porous carbon nanofiber can be easily produced on a large scale and can replace an expensive Pt-based material to serve as the stable and efficient catalyst for oxygen reduction reaction of the fuel cell.

The invention discloses a method for preparing novel carbon quantum dot / flower-shaped indium and calcium sulfide (CQDs / CaIn2S4) composite photocatalysts, and belongs to the field of environmental protection. The method includes preparing the CQDs / CaIn2S4 composite photocatalysts by the aid of in-situ hydrothermal processes at certain temperatures. The CQDs / CaIn2S4 composite photocatalysts prepared by the aid of the method can be applied to catalytically degrading tetracycline hydrochloride solution under the sunlight or visible light. The method has the advantages that the method includes simple technologies, is free of pollutant discharge in preparation procedures and is short in preparation period and low in energy consumption and cost, is a green synthesis technique, and the carbon quantum dot / flower-shaped indium and calcium sulfide composite photocatalysts can be prepared on a large scale; the visible light response and the adsorption capacity of the carbon quantum dot / flower-shaped indium and calcium sulfide composite photocatalysts can be improved after CQDs (carbon quantum dots) are compounded, the service lives of electrons-holes can be prolonged, photoelectron transmission can be promoted, and the visible light photocatalytic activity of the carbon quantum dot / flower-shaped indium and calcium sulfide composite photocatalysts can be greatly improved.

The invention discloses application of a hybridization perovskite meta-surface to Raman spectrum enhancement. The hybridization perovskite meta-surface is a hybridization perovskite film manufactured by metal halide and organic ammonium halide, metal in the metal halide is any one of Ge<2+>, Sn<2+> or Pb<2+>, and the organic ammonium in the organic ammonium halide is organic single ammonium ions or organic diammonium ions. The hybridization perovskite meta-surface can remarkably enhance the Raman spectrum of the surface molecules; besides, the hybridization perovskite meta-surface is simple to manufacture, and the raw materials are low in cost.

The present invention discloses a nitrogen-doped graphitization carbon encapsulation iron nanoparticle preparation method, which comprises: dissolving ammonium ferric citrate and dicyanodiamide in water, uniformly mixing, heating, removing the solvent to obtain solid powder, placing the solid powder in a quartz boat, placing into a tube type furnace provided with a quartz tube, introducing an inert gas, heating to a temperature of 500-1100 DEG C, maintaining for 0.5-7 h, cooling to a room temperature, treating the obtained solid for 12-36 h in an acid solution at a temperature of less than 100 DEG C, and carrying out filtration, water washing and drying to obtain the target material. According to the present invention, in the material, the size of the iron nanoparticles is 1-20 nm, the iron loading amount is 2-20 wt%, and the nitrogen doping amount is 1-10 wt%; the material has the high electrocatalysis activity when the material is applied for the proton exchange membrane fuel cell cathode oxygen reduction reaction; and the used precursor of the present method is inexpensive, the preparation process is simple, and the large-scale preparation can be achieved.

The invention discloses a preparation method of a slag-based geopolymer-iron oxide semiconductor composite catalyst and an application in dye degradation. The preparation method relates to two-step reaction of synthesis of the geopolymer and loading of iron oxide semiconductor, and is characterized in that the industrial solid waste slag is taken as raw materials and is synthetized into slag-based geopolymer binding material under the excitation of sodium silicate, and the slag-based geopolymer binding material is soaked in ferric nitrate water solution and is roasted to form the slag-based geopolymer-iron oxide semiconductor composite catalyst. The semiconductor composite catalyst is used in degradation reaction of photocatalytic congo red dye and methylene blue dye, the highest degradation rate can reach up to 100%, the degradation efficiency is high, and secondary pollution is not caused; and the semiconductor composite catalyst has a simple preparation process, is low in cost, and can realize large-scale preparation.

The invention discloses a method and device for carboxylation modification of carbon nano-material by ozone and a use thereof. The method utilizes solvent-assistant ozonolysis to realize carboxylation modification of a carbon nano-material and can greatly improve a ratio of a carboxyl functional group on the surface of the carbon nano-material. Through carbon nanotube sample ozonolysis modification aided by a sodium hypochlorite solution with a concentration of 5%, the highest ratio of carboxy groups of the modified carbon nanotubes to the total oxygen-containing groups is 71% or more, and a ratio of carboxyl groups of the sample un-modified by any solvents is only 54%. The method has the advantages of simple processes, low cost, high efficiency and environmental friendliness and has an important meaning for carbon nanotube functionalization and further chemical functionalization.

The invention provides a supported cobalt monatomic catalyst and a preparation method and application thereof. The preparation method comprises the following steps: (1) enabling urea to be subjected to a thermal polymerization reaction to obtain graphitized carbon nitride; (2) reacting the graphitized carbon nitride obtained in the step (1) with cobalt salt to obtain a cobalt and graphitized carbon nitride compound; and (3) carrying out heat treatment on the compound obtained in the step (2) and hypophosphite to obtain the supported cobalt monatomic catalyst. The preparation method is simple, wide in raw material source and high in yield, and has a large-scale application prospect. The supported cobalt monatomic catalyst is a phosphorus-doped graphitized carbon nitride supported cobalt monatomic catalyst, has the characteristics of adjustable band gap, high catalytic activity and high selectivity, and can realize selective oxidation under photocatalysis with high conversion rate; and the catalyst is especially suitable for converting alcohol compounds into aldehyde compounds or ketone compounds through a photo-oxidation catalytic reaction.

The invention discloses a method for preparing graphene through full liquid water phase physical stripping. The method comprises the following steps that (1) expanded graphite is soaked with water, and wetting soaking treatment is conducted; (2) the wetted and soaked expanded graphite is ground, and expanded graphite soaking liquid is obtained; (3) the expanded graphite soaking liquid is subjectedto high pressure homogeneity treatment, emulsification treatment and ultrahigh pressure critical treatment sequentially; and (4) standing is conducted till the liquid is layered, then spray drying isconducted, and graphene is obtained. The method adopts full liquid physical stripping, the solvent used in the method is water, so that the production process is energy-saving and environment-friendly; the raw materials used in the method are easy to get, no pollutants is generated in the preparation process, so that the preparation process is green and environmentally friendly, and cannot causeany pollution to the environment; the prepared graphene is intact in structure, contains a small amount of hydrophilic groups such as -OH, and has the good dispersing property; and graphene with different numbers of layers and specifications can be screened and prepared according to the requirement in different needed fields, so that graphene can be applied to different fields.

The invention relates to a method for preparing diamond coatings by using a SiC precursor method, which is characterized by comprising the following steps of: (1) treatment of base materials, (2) preparation of the SiC coatings, (3) treatment of the SiC coatings, (4) preparation of diamond coatings and (5) aftertreatment of the diamond coatings, wherein the aftertreatment adopts reduced carbon in the mixed air of CH4 and H2 to fill and densify the diamond coatings transformed from SiC in vacuum; and the flow ratio CH4:H2 of the air for filling and densifying is 1:98-99, the air pressure of the mixed air of the CH4 and the H2 in a reaction chamber during densifying reaction is 3-5 kPa, the temperature of a heat source for heating is higher than 2200 DEG C, the temperature of a basal body is 780-820 DEG C, and the filling and densifying time is not less than 30 min. The invention has the advantages of simple method, low cost, high speed and good consistency and compactness of settled layers.

The invention discloses a method for preparing titanium dioxide quantum dots by ultrasonication. The method is characterized in that titanium dioxide quantum dots are obtained by using a titanium dioxide precursor powder as a raw material and subjecting the titanium dioxide precursor powder to liquid nitrogen freeze embrittlement treatment and ultrasonication treatment. Aiming at the fact that theraw material is a titanium dioxide precursor powder with different morphologies and organization structures, the method of the invention realizes preparation of the quantum dots by liquid nitrogen ultra-low temperature freeze embrittlement treatment and ultrasonication treatment, and the process does not need complicated chemical modification and post treatment. The prepared quantum dots are in eigenstate. The preparation process is simple, the equipment requirements are low, operation is convenient and the cost is low, and therefore the method is beneficial to batch preparation of the titanium dioxide quantum dots.

The invention provides a method of preparing graphene oxide / ferroferric oxide composite material under normal pressure. The method includes following steps: mixing graphene oxide polyol dispersion liquid, ferric iron source, alkaline regulator, surfactant and promoter to obtain a mixed solution; at normal pressure, allowing thermal reaction of the mixed solution obtained in the above step to obtain the graphene oxide / ferroferric oxide composite material. By adding active substance and improving production process, preparing of the graphene oxide / ferroferric oxide composite material through thermal reaction at low pressure and low temperature is realized, uniform distribution of ferroferric oxide is realized, and aggregation of graphene oxide is avoided effectively; no high-harm reductant is used, so that environment pollution is avoided. The method is simple in process, easy in operation and capable of realizing large-scale preparing.