377 results about "Graphene nanocomposites" patented technology

A composite composition for electrochemical cell electrode applications, the composition comprising multiple solid particles, wherein (a) a solid particle is composed of graphene platelets dispersed in or bonded by a first matrix or binder material, wherein the graphene platelets are not obtained from graphitization of the first binder or matrix material; (b) the graphene platelets have a length or width in the range of 10 nm to 10 μm; (c) the multiple solid particles are bonded by a second binder material; and (d) the first or second binder material is selected from a polymer, polymeric carbon, amorphous carbon, metal, glass, ceramic, oxide, organic material, or a combination thereof. For a lithium ion battery anode application, the first binder or matrix material is preferably amorphous carbon or polymeric carbon. Such a composite composition provides a high anode capacity and good cycling response. For a supercapacitor electrode application, the solid particles preferably have meso-scale pores therein to accommodate electrolyte.

A nanographitic composite for use as an anode in a lithium ion battery includes nanoscale particles of an electroactive material; and a plurality of graphene nanoplatelets having a thickness of 0.34 nm to 5 nm and lateral dimensions of less than 900 nm, wherein the electroactive particle has an average particle size that is larger than the average lateral dimension of the graphene nanoplatelets, and the graphene nanoplatelets coat at least a portion of the nanoscale particles to form a porous nanographitic layer made up of overlapping graphene nanoplatelets.

The invention relates to a titanium dioxide/graphene nanocomposite material, a preparation method of the nanocomposite material and application of the nanocomposite material in the field of energy source and cleaning environment. The graphene accounts for 1-25wt% and the balance is titanium dioxide. Morphology of the titanium dioxide is a mesoporous structure or a structure with a dominant high energy surface, and titanium dioxide is scattered uniformly on the surface of graphene. According to the invention, by adopting a titanium source and graphene as initial materials, and water or organic solvents as reaction solvents, the nanocomposite material with titanium dioxide with the mesoporous structure or a titanium dioxide nano sheet with the dominant high energy surface compounded with graphene can be obtained through hydrothermal synthesis or a hydrolysis reaction. The invention can be carried out in an aqueous solution system and the crystallinity of the product is high. The composite material can be applied to a cathode material of a power ion battery, has a higher charge-discharge capacity, is excellent in high current charge and discharge, stable in circulating performance, has very good photocatalytic performance and can be used to light degradation of organic pollutants and water photolysis for preparing hydrogen.

The invention relates to a preparation method of a silicon/graphene nanocomposite material for a cathode of a lithium ion battery, which comprises the steps of: preparing oxidized graphite; preparing a silica/ graphene nanocomposite material under the existence of a surfactant; then preparing the silicon/graphene nanocomposite material for the cathode of the lithium ion battery through the magnesiothermic reduction reaction. Compared with the prior art, the graphene in the composite material, prepared by the invention, can better inhibit volumetric expansion of silicon material in the insertion and separation process of lithium ions so as to improve the circulating performance of the composite material greatly, so that the volume of the material after 30 circulations under the current of 200mA/g is still maintained to be above 1100mAh/g.

The invention relates to a nylon 6/graphene nanometer composite material with high thermal conductivity and a preparation method thereof. The composite material is composed of a nylon 6 matrix and nanometer graphene and is prepared by carrying out in situ polymerization and melt blending and banburying on obtained master batches and pure nylon 6. The nanometer graphene oxide adopted in the preparation method has a high radius-thickness ratio, a small amount of nanometer graphene oxide is added and is thermally reduced to form heat-conducting master batches, and an effective graphene heat conducting path can be formed effectively in the nylon 6. The small amount of nanometer graphene oxide heat conducting fillers and the master batches are added into the pure nylon 6 to be mixed and compounded so as to keep the good mechanical properties of the nylon 6 in the heat-conducting composite material. The nylon 6/graphene nanometer composite material with high thermal conductivity, provided by the invention, is excellent in heat conducting property, simple in preparation process and low in cost, thereby being capable of being widely applied in the field of heat dissipation of automobiles, computers, LEDs (Light Emitting Diode), etc.

Disclosed is a facile and cost effective method of producing nano silicon powder or graphene-doped silicon nano powder having a particle size smaller than 100 nm. The method comprises: (a) preparing a silicon precursor/graphene nano composite; (b) mixing the silicon precursor/graphene nano composite with a desired quantity of magnesium; (c) converting the silicon precursor to form a mixture of graphene-doped silicon and a reaction by-product through a thermal and/or chemical reduction reaction; and (d) removing the reaction by-product from the mixture to obtain graphene-doped silicon nano powder.

The invention discloses a polypyrrole/graphene nano composite which belongs to the technical field of composites. In the invention, ethanol is taken as a medium, para-toluenesulfonic acid is taken as a surface active agent, polyethylene glycol-400 is taken as phase transfer catalyst, FeCl3*6H2O is taken as an evocating agent, and under ultrasound conditions, pyrrole monomers are polymerized in situ on graphene, so as to obtain the polypyrrole/graphene nano composite. In the composite of the invention, through analysis by electron microscopy, the pyrrole monomers are polymerized in situ and evenly cover the grapheme, and the graphene and the polypyrrole are tightly combined in a nano level; and thermogravimetric analysis and electric conductivity study show that the composite has better heat stability, electric conductivity and processability and can be used in the fields of sensors, electron devices and biomedicine.

The invention discloses a metal/grapheme nanocomposite and a preparation method thereof. The method comprises a photo-reduction one-step method and a photocatalytic reduction one-step method. The photo-reduction one-step method comprises the steps as follows: a grapheme oxide and metal complex acid or inorganic salt and a photo-reduction agent are mixed at the room temperature or under the condition of an ice-water bath, and under the light condition, organic negative hydrogen donors reduce metal ions and the grapheme oxide, so that a product is obtained. One approach of the photocatalytic reduction one-step method comprises the steps as follows: the grapheme oxide and the metal complex acid or salt are mixed in a DMF (dimethyl formamide) water solution containing a reducing agent, a metal ligand and a photocatalyst or in a water solution, catalysis is performed through the catalyst under the light condition, and at the same time, the reducing agent reduces the metal ions and the grapheme oxide, so that a product is obtained; and the other approach of the photocatalytic reduction one-step method comprises the steps as follows: the grapheme oxide and a metal organic complex are mixed in a DMF water solution containing the reducing agent and the photocatalyst or in a water solution, then catalysis is performed through the catalyst under the light condition, and the reducing agent reduces the metal organic complex and the grapheme oxide, so that a product is obtained.

Belonging to the technical field of chemical material preparation, the invention relates to a preparation method of a Co3O4/graphene nanocomposite material. The method provided in the invention is characterized by: first employing a simple chemical method to synthesize Co3O4 nanoparticles under the protection of a surfactant, then adsorbing oxidized graphene on surfaces of the Co3O4 nanoparticles uniformly by means of the interaction between the surfactant and the oxidized graphene, and reducing the oxidized graphene, thus forming the uniform Co3O4/graphene nanocomposite material. Good electrical conductivity is achieved among Co3O4 nanoparticles through graphene, so that the electroconductibility of the composite material can be improved. The Co3O4 nanoparticles in the composite material have a size of 50-100 nanometers, and account for 60%-95% by weight. The method provided in the invention does not involve environmentally harmful materials, and the process is simple, practicable and easy to operate. The prepared Co3O4/graphene nanocomposite material has high specific capacity and capacitance, as well as good cycle performance, thus having good application prospects in the fields of lithium ion batteries and supercapacitors.

The present disclosure provides a method for producing a manganese oxide/graphene nanocomposite including synthesizing a manganese oxide/graphene nanocomposite through liquid phase reaction at a room temperature, a manganese oxide/graphene nanocomposite produced by the method, and an electrode material and a super-capacitor electrode including the manganese oxide/graphene nanocomposite.

The invention discloses a preparation method for a high-dielectricity polyvinylidene fluoride/poly-dopamine-coated graphene nanocomposite. The method comprises the following steps: graphene oxide is prepared through a Hummers oxidation method, dopamine is automatically polymerized under the alkaline condition to coat the surface of the graphene oxide, reduction is performed on the poly-dopamine graphene oxide through hydrazine hydrate, centrifugal washing is performed repeatedly for removing impurities, the obtained poly-dopamine-coated grapheme can disperse in N, N-dimethylformamide well after being subjected to ultrasonic treatment, the polyvinylidene difluoride and the poly-dopamine-coated graphene are mixed through a solution method, and hot press molding is performed on the mixture, so that the nanocomposite is obtained. The preparation process is simple and easy to operate, the repeatability is good, the composite is good in flexibility and machinability, and has high potential for being applied to dielectric materials of energy storage parts such as capacitors.

A preparation method of polyaniline/graphene controllable load platinum nanoparticles comprises the following steps of: (1) preparing reduced grapheme; (2) synthesizing a polyaniline/reduced grapheme (PANI/rGNS) nanocomposite by a liquid-liquid interfacial method; (3) preparing a platinum loaded polyaniline/graphene (Pt/PANI/rGNS) nanocatalyst. The invention has the following advantages: by the adoption of the liquid-liquid interfacial polymerization method, the uniformly dispersed PANI/rGNS nanocomposite is synthesized, thus effectively preventing the agglomeration of the composite material,making for uniformly and controllably loading PtNPs on the surface of PANI/rGNS, solving the technical difficulty of metal particle agglomeration and realizing uniform and efficient loading of PtNPs;an electrochemical test result shows that the catalyst has excellent electrocatalytic activity for methanol oxidation and oxygen reduction and ultrasensitive detection of hydrogen peroxide (H2O2) andglucose can be also realized.

A nanocomposite material formed of graphene and a mesoporous metal oxide having a demonstrated specific capacity of more than 200 F/g with particular utility when employed in supercapacitor applications. A method for making these nanocomposite materials by first forming a mixture of graphene, a surfactant, and a metal oxide precursor, precipitating the metal oxide precursor with the surfactant from the mixture to form a mesoporous metal oxide. The mesoporous metal oxide is then deposited onto a surface of the graphene.

The invention discloses a graphene/nylon 6 fiber with flame-retarding and ultraviolet-proof properties and a preparation method of the graphene/nylon 6 fiber and belongs to the technical field of functional high molecular materials. The graphene/nylon 6 fiber with the flame-retarding and ultraviolet-proof properties is prepared through high-speed melting spinning of a graphene/nylon 6 nano composite material; the graphene/nylon 6 nano composite material is prepared by compounding modified graphene, caprolactam and various auxiliary agents. The graphene/nylon 6 nano composite material obtained by the invention can continuously pass through a melting spinning hole at a high speed and continuous high-speed spinning is realized; the diameter of the fiber is 5mum to 50mum; compared with a pure nylon 6 fiber, the prepared graphene modified nylon 6 fiber has excellent flame-retarding, melt-dripping-resisting and ultraviolet-proof performances and the like.

The invention discloses a CuO-Cu2O/graphene nano compound material and a preparation method thereof. The CuO-Cu2O/graphene nano compound material disclosed by the invention is characterized in that CuO-Cu2O nano spheres are uniformly dispersed on the surface of graphene, are of a hollow structure, and comprise CuO nano crystals and Cu2O nano crystals through mixing. The preparation method comprises the following steps: mixing a defined amount of a copper slat and graphite oxide, dispersing to form a uniform solution, and adding a defined amount of ammonia water for adjusting a pH value; then placing a mixed solution in a microwave reactor, and performing a microwave heating reaction to prepare a precursor; and finally, calcining the precursor in an inert atmosphere at a high temperature of 450-700 DEG C for 1-3 hours, and calcining the precursor in an air atmosphere at a low temperature of 150-250 DEG C for 1-2 hours to obtain the CuO-Cu2O/graphene nano compound material. The CuO-Cu2O/graphene nano compound material disclosed by the invention is simple in preparation process, low in cost, and good in electrochemical property, and can be applied to a lithium battery electrode.

The invention provides preparation and application of an alpha fetoprotein and carcino-embryonic antigen electrochemiluminescence sensor, and belongs to the technical fields of nano function material, clinical analysis, a bioseneor technology and electrochemistry. The characteristics that platinum nanoparticle @meso-porous silicon @ graphene nanocomposite (PtNPs@m-Si@GS) is strong in conductivity, good in stability, large in specific surface area, good in biocompatibility, strong in catalytic activity and the like are utilized in preparation; an alpha fetoprotein second antibody (anti-alpha fetoprotein (AFP)) and a carcino-embryonic antigen secondary antibody (anti-carcino-embryonicantigen (CEA)) are marked, so as to prepare the marked second antibodies Ru-PtNPs@M-Si@GS/anti-AFP and luminol-PtNPs@M-Si@GS/anti-CEA; and the sensitivity of the sensor is obviously improved. Compared with other single-channel electrode sensors, alpha fetoprotein and carcino-embryonic antigen can be simultaneously detected on a same electrode at one time; the detection efficiency is obviously improved; and the alpha fetoprotein and carcino-embryonic antigen electrochemiluminescence sensor has important scientific significance and application value on clinical early diagnosis of hepatic carcinoma.

The invention relates to a method for preparing graphene, a method for carrying out graphene surface modification by taking one or more than two of pyrene, pyrene derivatives, naphthalene and naphthalene derivatives as a modifying agent as well as a method for manufacturing TiO2-graphene nano-composite material by utilizing the reaction of the surface-modified graphene and a titanium-containing compound and a product thereof. The method for preparing graphene comprises the steps of (a1) reducing dispersive graphite oxide in inert solvent by using a reducing agent to form a graphene-containing reaction mixture, wherein the reducing agent comprises sodium borohydride, vitamin C or combination thereof; and (a2) isolating graphene from the reaction mixture. The obtained graphene is flocculent and the TiO2-graphene nano-composite material has efficient photocatalytic performance.

A nanocomposite material comprises polyethylene terephthalate (PET) as a base polymer and a nanoparticle that increases the strength of the base polymer.

The invention discloses a zinc oxide nanowire-graphene gas sensor and a preparation method thereof, and belongs to the technical field of gas detection. The gas sensor consists of a substrate, an interdigital electrode and a gas sensitive coating, wherein the gas sensitive coating is made of a zinc oxide nanowire-graphene composite material. The preparation process of the sensor comprises the following steps: (1) preparing the zinc oxide nanowire-graphene nano-composite material; (2) machining and preparing the interdigital electrode on the substrate by a micromachining method and covering the surface of the interdigital electrode with a layer of nano-composite material serving as the gas sensitive coating to form a sensing device. The lower detection limit of the gas sensor to ammonia gas under room temperature reaches 50 ppb; meanwhile, the gas senor is shorter in response time, higher in repeat stability and higher in gas selectivity. The gas sensor is suitable for performing high-sensitivity detection on the ammonia gas under the room temperature.

The invention discloses a platinum (Pt)/reduced graphite oxide (RGO) nano composite material and a preparation method and application thereof. According to the preparation method, graphite oxide (GO) and a platinum metal precursor are reduced in one step by radiation and induction of a gamma ray or an electronic beam, thus obtaining the Pt/RGO nano composite material with the Pt load capacity being 1.0wt% to 15wt%; Pt nano particles are uniformly distributed on an RGO sheet layer, and the average diameter of the Pt nano particles is 1.8 nanometers; and the particle sizes of the Pt nano particles are within 2 nanometers. By virtue of the load capacity of the nano particles of platinum metal, the reducing degree of the GO can be increased, the conductivity of a product is improved, and the surface utilization rate of the RGO sheet layer is increased. Compared with the GO and pure graphene, the nano composite material prepared by the method has higher specific capacitance and higher high-current multiplying power when being applied to a super-capacitor electrode material.

The invention belongs to the field of materials and relates to a method for preparing a poly 1,5-diamino-anthraquinone modified graphene nanometer composite material. The method comprises the following steps: (1) slowly adding an acid organic solution containing an oxidizing agent into acid sol containing a 1,5-diamino-anthraquinone monomer and graphite oxide; (2) reacting the mixed sol at a constant temperature, thereby obtaining an intermediate product; (3) washing the intermediate product by using deionized water until the filtrate is neutral; (4) reducing the product obtained in the step (3); (5) washing the precipitate obtained in the step (4) by using the deionized water, and performing centrifugal separation, thereby obtaining powder; (6) performing vacuum drying, thereby obtaining the 1,5-diamino-anthraquinone modified graphene nanometer composite powder. The cost is low, the scheme is simple and feasible, and the synthetic 1,5-diamino-anthraquinone modified graphene nanometer composite material can be widely applied to the fields of secondary batteries, supercapacitors, microwave absorption coatings and sensors.

The invention discloses a SiC-graphene nano-composite and a preparation method thereof. The SiC-graphene nano-composite has a core-shell structure with the core covered with the shell, wherein the core is made of SiC nano particles, and the shell is made of nano graphite composed of the graphene. The preparation method includes steps of (1) precursor pyrolysis: heating and pyrolyzing the polymer pyrolysis into SiC nano particles at the inert gas atmosphere in a chemical gas-phase deposition furnace; (2), chemical gas-phase deposition: heating continuously until silicon atoms on surfaces of the SiC nano particles are sublimed and escape, forming graphite fragments by means of recombination of the residual carbon atoms, and finally obtaining the SiC-graphene nano-composite by deposition and growth of the graphite fragments. The SiC-graphene nano-composite has the advantages of excellent physical and chemical properties and mechanical properties, simplicity in preparation process, low cost and wide application range.

The invention relates to a method for manufacturing a porous flaky NiCo2O4 and grapheme composite capacitive material, and belongs to the field of nano composite material manufacturing. According to the method, a graphite oxide, cobalt nitrate and nickel nitrate are dissolved in deionized water in an ultrasonic mode and stirred, a certain amount of hexamethylene tetramine is added, a reflux reaction is carried out for 3-4 hours at the temperature of 90 DEG C, sediments are collected, the collected sediments are calcined in an air atmosphere for 2 hours at the temperature of 330 DEG C, and the porous flaky NiCo2O4 and grapheme nano composite material is obtained. In the manufactured porous flaky NiCo2O4 and grapheme composite capacitive material, porous flaky NiCo2O4 is completely attached to the surface of a grapheme piece. By means of the composite structure, conductivity of the material is improved, and the contact area of the material and an electrolyte solution is greatly improved, so that the composite material has high specific capacitance and good electrochemical stability and can be possibly used as a super-capacitor electrode material.

The invention provides a method for 1T-phase molybdenum disulfide/graphene nano composite material by a hydrothermal process. Oxidized graphene, a molybdenum source, a sulfur source and a reducing agent are respectively used as reactants to synthesize the 1T-phase molybdenum disulfide/graphene nano composite material through hydrothermal reaction. The method is low in raw material cost and simplein operation, and one-step preparation of the 1T-phase molybdenum disulfide/graphene nano composite material can be realized through the hydrothermal reaction. In addition, due to simplicity in preparation, high product yield, mild reaction conditions, product stability, less proneness to phase change and the like, a promising application prospect is realized.