1410results about "Graphene" patented technology

The invention discloses a paper-based electrode based on liquid metal assisted laser-induced graphene and a preparation method thereof.The paper-based electrode comprises a substrate layer, a functional layer, a conductive layer and a hydrophobic layer which are sequentially arranged, the substrate layer is made of paper, the functional layer is formed by coating liquid metal nanoparticles, and the conductive layer is formed by coating liquid metal nanoparticles. The conductive layer is an electrode formed by a laser-induced graphene technology, and the hydrophobic layer is a fluid control area formed by wax packaging. According to the invention, paper is used as a substrate, liquid metal is combined with a laser-induced graphene technology, surface modification is carried out through eutectic gallium indium (EGaIn), polyimide (PI) and N-methyl pyrrolidone (NMP) composite slurry, and then a conductive electrode pattern is formed on the surface of the paper substrate by using a laser-induced graphene (LIG) technology. The method has the advantages of simple preparation, low cost, environmental friendliness and the like, and the prepared paper-based electrochemical biosensor has excellent conductivity, mechanical flexibility and electrochemical activity.

The invention provides a magnetic confinement microwave plasma preparation method and system for coal-based graphene quantum dots, and relates to the technical field of graphene quantum dot preparation, and the method comprises the following steps: pretreating a coal raw material, removing impurities, and crushing the coal raw material to a preset particle size; detecting the coal quality parameters of the pretreated coal raw material, wherein the coal quality parameters at least comprise the contents of C, H and O elements; the coal quality parameters are input into a QYOA algorithm to be analyzed, and adjustment parameters of microwave power and reaction gas are obtained; feeding the pretreated coal raw material into a reaction cavity, and forming a three-dimensional confinement field in the reaction cavity through a magnetic confinement device; according to the method, magnetic confinement, microwave plasma, a QYOA algorithm and ultrasonic aftertreatment are organically combined to form a synergistic effect, dissociation of carbon clusters is promoted through the synergistic effect of the magnetic confinement and the microwave plasma, the yield of the coal-based graphene quantum dots is increased to 30% or above from less than 10% of a traditional method, the production efficiency is improved, and large-scale production is facilitated.

The invention discloses a high-valued utilization method of waste biomass, which comprises the following steps: firstly, applying current to the waste biomass containing carbon element to generate Joule heat, and generating a high-temperature environment in an extremely short time, so as to realize rapid carbonization of the biomass; then conductive carbon black or other auxiliaries do not need to be additionally added, current is applied again to generate Joule heat, a higher-temperature environment is generated within an extremely short time, and graphitization transformation of the biochar is achieved. Compared with traditional pyrolysis, hydrothermal, roasting or chemical vapor deposition methods, the flash Joule thermal method has the advantages of being easy and convenient to operate, short in consumed time, low in energy consumption, high in efficiency, high in safety, environmentally friendly and the like, and is suitable for high-value utilization of various biomass resources and green preparation of graphene materials.

The invention relates to the technical field of graphene processing, and particularly discloses a nano graphene powder preparation method which comprises the following steps: weighing a graphite raw material; opening a discharge valve of the feeding cabin, and feeding the graphite raw material into the pressure stabilizing cabin; a graphite raw material is sucked into a first-stage jet mill high-pressure cabin from a pressure stabilizing cabin, first-stage jet milling is conducted, and a first-stage abrasive material is obtained; the first-stage grinding material with the thickness not larger than 10 micrometers is conveyed to a second-stage jet mill high-pressure cabin; processing the first-stage abrasive material by a second-stage jet mill high-pressure cabin to obtain a second-stage abrasive material; the second-stage grinding material with the thickness not larger than 100 nanometers is conveyed to a flow energy depolymerization cabin; the flow energy depolymerization cabin is used for processing the secondary grinding material, and nano graphene powder is obtained through screening; the high-purity graphite raw material is processed through a three-stage gradient processing framework, a negative feedback regulation scheme is introduced in each processing link, the quality of products in different stages is controlled, a progressive processing technology is constructed, and the product rate is greatly increased.

The invention relates to a large-breadth flexible damage sensing material and a preparation method thereof, belongs to the field of intelligent material preparation, and solves the problem that large-scale preparation of the large-breadth flexible damage sensing material is difficult in the prior art. The invention discloses a large-breadth flexible damage sensing material and a preparation method thereof. The large-breadth flexible damage sensing material comprises a flexible substrate layer, a conductive layer and a packaging layer, wherein the conductive layer is superposed on the flexible substrate layer; the packaging layer covers the conductive layer; the conductive layer is made of a laser-engraved polyimide film, a functional laser-induced graphene structure and an auxiliary separation structure which are etched by a laser engraving machine are arranged on the conductive layer, and the auxiliary separation structure comprises a film through hole and an edge cutting line; the large-breadth flexible damage sensing material provided by the invention is high in fineness, stable in performance and capable of meeting large-breadth sensing application, the preparation method of the large-breadth flexible damage sensing material is simple in step and high in preparation efficiency, and the large-breadth flexible damage sensing material which is stable in performance and high in fineness can be prepared in batches.

The invention discloses a NiCu-based alloy catalyst for preparing high-value products through natural gas decarbonization and application of the NiCu-based alloy catalyst, and belongs to the technical field of natural gas high-value catalytic conversion. The preparation method of the NiCu-based alloy catalyst comprises the following steps: (1) adding nickel nitrate hexahydrate and urea into hot water, adding ethylene glycol, carrying out a stirring reaction at 120-150 DEG C, and calcining the obtained intermediate to obtain a nickel oxide precursor; (2) adding a copper nitrate aqueous solution and ammonia water into the nickel oxide precursor, so that copper ions are anchored on the surface of nickel oxide, drying and calcining to obtain a Ni-Cu alloy oxide precursor; and (3) adding the Ni-Cu alloy oxide precursor, bismuth trioxide and metallic tin into deionized water, adding a complexing agent, carrying out ultrasonic treatment, and carrying out H2 reduction calcination on the obtained precipitate to obtain the Ni < x > Cu < y > Bi < z > Snm alloy. The NiCu-based alloy catalyst is used in a natural gas decarburization high-value product preparation reaction, and the natural gas decarburization reaction is sufficient, and long-term efficient conversion and stable operation are achieved by combining the synergistic effect of ultrasonic waves and an alternating magnetic field.

The present invention provides a graphene-containing laminate comprising. in order: a substrate: a graphene layer structure: a first metal oxide layer formed of a first metal oxide, wherein the first metal oxide is a transition metal oxide: and a second metal oxide layer formed of a second metal oxide: wherein the first metal oxide layer has a thickness of from 0.1 nm to 5 nm; and wherein the first metal oxide layer has a work function of 5 eV or more.

The invention belongs to the technical field of semiconductor oxide gas sensors, and particularly relates to an rGO / CuO / Li sensitive material, a preparation method thereof and application of the rGO / CuO / Li sensitive material in H2S sensors. The preparation method comprises the following steps: firstly, preparing a graphene oxide nanosheet by using an improved Hummers method, and then preparing the rGO / CuO / Li sensitive material by using copper nitrate, lithium chloride and the prepared graphene oxide nanosheet as raw materials, polyvinylpyrrolidone as a surfactant and N, N-dimethylformamide as a solvent by using a one-step solvothermal method. Under the condition of room temperature, the sensitive material shows a relatively high response value (220.1) and a relatively low detection lower limit (1ppb) on hydrogen sulfide, has good selectivity, repeatability and stability, and has a wide application prospect in trace-level hydrogen sulfide detection in the fields of industrial safety and atmosphere detection.

The invention relates to the technical field of batteries, in particular to a low-hydrogen-evolution graphene material for a lead-acid battery and a preparation method thereof.The method comprises the steps that firstly, ethidene diamine is grafted to the surface of graphene oxide through a carbodiimide / active ester method, and aminated graphene is obtained; performing heat treatment in a nitrogen / ammonia gas atmosphere to realize nitrogen doping; compounding with titanium dioxide, and carrying out hydrothermal reaction to form a stable structure; then, sequentially grafting imidazolium silane and perfluorodecyl silane to carry out hydrophobic modification; and finally, stabilization and low-temperature re-nitridation curing are carried out through titanium tetrabutoxide. The graphene material prepared by the method endows the battery with excellent performance, and is low in direct-current internal resistance and high in capacity retention ratio.

The invention relates to a multi-conductive-agent composite conductive paste for a lithium battery and a preparation method of the multi-conductive-agent composite conductive paste, and belongs to the technical field of lithium battery conductive pastes.The multi-conductive-agent composite conductive paste is characterized in that an iron-molybdenum catalyst is loaded on expanded graphite, then vertical orientation carbon nanotubes and transverse graphene blades are grown in situ, the specific surface area is increased, and the expanded graphite serves as a layered carrier; a metal alloy catalyst can be uniformly loaded in natural pores of the carbon nanotube, a layered framework is kept from collapsing at a high temperature, support is provided for directional growth of a carbon material, electrons can be rapidly transmitted along the carbon nanotube when the composite conductive paste is prepared, gaps of the carbon nanotube are filled by graphene blades, a breakpoint-free conductive network is formed, and the composite conductive paste is prepared. And meanwhile, abundant pores provide channels for lithium ion diffusion, so that the conductive efficiency is improved from the source of the structure, and abundant specific surface area and subsequent nitrogen and sulfur loading provide sufficient sites.

The invention discloses a graphene quantum dot material as well as a preparation method and application thereof, and belongs to the technical field of biomedical materials. The preparation method comprises the following steps: S1, carrying out hydrothermal reaction on a mixed solution of mesoporous SiO2 and a carbon source to obtain a product I; s2, the product I and a fluoride solution are mixed to remove SiO2, and a product II is obtained; and S3, refining the product II to obtain the graphene quantum dot material. The carbon source is selected from at least one of triammonium citrate, diammonium hydrogen citrate, citric acid, folic acid, urea, thiourea and dicyanodiamine; the fluoride is selected from ammonium bifluoride and / or hydrogen fluoride. The particle size of the graphene quantum dot material provided by the invention is 15-30nm, the distribution is controllable, and the raw materials are easy to obtain; the prepared platinum nanoparticle / graphene quantum dot composite nanomaterial is high in solubility, stable in physical and chemical properties and remarkable in chemotherapy effect.

The invention relates to a graphene oxide modified cement-based grouting material as well as a preparation method and application thereof. The graphene oxide modified cement-based grouting material is prepared from cement, graphene oxide, silica fume, a polycarboxylate superplasticizer, an accelerator and water. The invention also provides a preparation method of the graphene oxide modified cement-based grouting material, which comprises the following steps: adding GO into an aqueous solution containing a polycarboxylic acid water reducer, stirring and then carrying out ultrasonic treatment to form a GO suspension; premixing silica fume and cement to obtain a dry mixture; and adding the GO suspension into the dry mixture, mixing and stirring, and then doping an accelerator to obtain the graphene oxide modified cement-based grouting material. The invention further provides application of the graphene oxide modified cement-based grouting material as a reinforcement treatment material for loose accumulation bodies and broken rock stratums. The GO modified grouting material solves the problem that the performance of a cement-based material is affected due to the fact that GO is not uniformly dispersed and larger aggregates are easily formed in the existing GO modified grouting material.

The invention belongs to the technical field of functional films, and particularly relates to a preparation method of a high-thickness graphene heat conduction film. Comprising the following steps: (1) low-functionalized graphene powder is taken as a raw material, the content of an additive in the raw material is not more than 20wt%, and the solvent content is not more than 10wt%; (2) carrying out hot press molding on the raw materials in the step (1) at the temperature of 25-300 DEG C to obtain a dense graphene thick film; and (3) carrying out heat treatment on the dense graphene thick film in the step (2) in an atmosphere furnace with the temperature of 1000-3300 DEG C for a certain time to ensure interlayer ordering and crystal graphitization, so as to obtain the graphene heat-conducting film with high thickness and high heat conductivity, the thickness of the graphene heat-conducting film can reach more than 200 microns, and the heat conductivity of the graphene heat-conducting film can reach more than 1300W / mK. The preparation method is simple in operation process, low in cost, easy in scale amplification and suitable for preparation and performance improvement of the ultra-high-thickness graphene heat-conducting film, and the application range of the graphene film in the fields of heat management, electromagnetic shielding, nuclear technology, high-end instrument equipment and the like is widened.

The invention provides an MOF-rGO composite modified zinc negative electrode as well as a preparation method and application thereof. The preparation method comprises the following steps: preparing rGO dispersion liquid by taking GO as a raw material, and loading rGO in the rGO dispersion liquid to the surface of zinc foil by adopting an L-B self-assembly method to obtain rGO modified zinc foil; and carrying out first impregnation on the rGO modified zinc foil in a zinc salt solution, and then carrying out second impregnation in an organic ligand solution to obtain the MOF-rGO composite modified zinc negative electrode. Directional arrangement of rGO on the surface of the zinc foil is achieved through L-B self-assembly, the obtained rGO modification layer is compact and stable, MOF is synthesized on the surface of the material in situ without using a binder on the basis, growth of dendritic crystals is effectively inhibited through the synergistic effect that rGO provides a conductive network and MOF regulates and controls zinc ion diffusion, and the preparation method has the advantages that the preparation process is simple, and the preparation cost is low. Therefore, the cycle performance and the energy density of the battery are remarkably improved, the short circuit of the battery is reduced, and industrial mass production is adapted.

The invention discloses a high-activity nitrogen-doped hard carbon negative electrode material and a preparation method thereof, high specific capacity is obtained, the problem that the initial coulombic efficiency of existing hard carbon is not high is solved, a prepared product is good in conductivity and high in activity, the capacity is high when the product is used as a lithium ion battery, and the obtained material mainly has the following characteristics that (1) the specific capacity is high and is 190-260mAh / g; (3) first coulombic efficiency gt; 80%.

The invention relates to the technical field of die steel materials, in particular to an injection molding die steel material and a preparation method thereof.The preparation method comprises the following steps that firstly, raw materials including, by weight, 0.3%-0.5% of C, 1.2%-1.5% of Mn, 3.3%-3.5% of Cr, 0.7%-0.9% of Si, 0.4%-0.5% of V, 0.1%-0.2% of Ni, 0.01%-0.03% of B and the balance Fe are weighed; according to the injection mold steel material, C, Mn, Cr, Si and other raw materials are blended, smelted, poured and formed, meanwhile, ultrasonic treatment of a synergistic solution is matched, solid solution, water cooling and tempering improvement treatment are carried out, the operation steps can homogenize the structure, stabilize the structure and optimize the toughness and other performance of a product, finally, homogenization treatment is carried out, and through continuous and coordinated improvement in the process, the product quality is improved. The fracture toughness, thermal conductivity and wear resistance of the obtained product are harmoniously improved, and the product is resistant to different degrees of corrosion stability.

The invention relates to the technical field of lithium ion battery positive electrode materials, and discloses a double-doped double-coated lithium iron phosphate positive electrode material and a preparation method thereof. The positive electrode material sequentially comprises a Mg < 2 + > and Ti < 4 + > co-doped lithium iron phosphate core, a lithium phosphate ion conductor coating layer and a graphene conducting layer from inside to outside. The preparation method comprises the following steps: mixing raw materials containing iron, phosphorus, lithium, magnesium and titanium sources, and carrying out ball milling, spray drying and two-stage sintering to obtain a doped inner core; and then sequentially carrying out high-pressure rolling pretreatment, lithium phosphate coating heat treatment and graphene chemical vapor deposition on the inner core to finally prepare the positive electrode material. Through the synergistic effect of core co-doping, high-pressure rolling morphology control and a surface double-coating structure, the prepared lithium iron phosphate positive electrode material has high compaction density, conductivity, gram volume under high magnification and cycling stability at the same time.

The invention discloses a preparation method of a graphene composite coating with multifunctional characteristics, which comprises the following steps: processing a substrate, coating a carbon source polymer solution on the surface of a substrate material to form a polymer liquid film, and treating a polymer to form a polymer film; laser induction: carbonizing the polymer film by using laser to form a laser-induced graphene (LIG) coating; functional particles are added, nanoparticles are doped on the surface of the LIG coating in a coating mode, and a composite structure is formed; integrating the multifunctional coating, and forming the graphene-based multifunctional composite coating through post-treatment.

The application belongs to the technical field of graphene material preparation, and particularly relates to a general covalent functionalized graphene (CFG) electrochemical preparation method, which comprises the following steps: (1) under the condition of a light sealing oil seal, graphite electrodes are subjected to electrochemical intercalation treatment by using concentrated sulfuric acid; (2) after the intercalation is completed, light sealing oil is injected into an electrolytic cell while the concentrated sulfuric acid is discharged; (3) in the electrolytic cell, a micro-liquid film reaction zone is constructed by using the density and phase solubility difference of the light sealing oil, the aqueous electrolyte and the heavy sealing oil, and the micro-liquid film reaction zone is contacted with the intercalated graphite electrode to make the intercalated graphite electrode electrochemically oxidized to generate CFG; (4) by controlling the relative intercalated graphite electrode of the micro-liquid film reaction zone to move directionally, the whole intercalated graphite electrode is gradually and completely converted into CFG; (5) the CFG structure after the reaction is placed into a solvent to be mechanically exfoliated to prepare a CFG dispersion liquid, and the CFG powder is obtained after drying treatment.

The invention discloses a graphene-based heat conduction film with a stable interface and a preparation method of the graphene-based heat conduction film. When the graphene film is prepared, a substrate with a reticulate pattern structure with a specific size is utilized, on one hand, separation of a graphene oxide precursor film with high surface energy from a matrix is facilitated, and on the other hand, more stable nucleation sites and interlocking interfaces are provided for in-situ growth of subsequent carbides. According to the in-situ growth method, a layer of superhard carbide coating which is compact in structure and is combined through strong chemical bonds can be generated on the surface of graphene in situ, the carbide coating can form a superstable interface with graphene, the graphene film is effectively protected, and the abrasion resistance, impact resistance and space environment erosion resistance of the graphene film are greatly improved.

A sensor device including a conductive graphene film covered on at least one side by a graphene support layer of parylene, a detection element configured to sense an environmental change, and an electrode. The parylene repairs some defects of the conductive graphene film without damaging, polluting, or degrading the conductivity of conductive graphene film.

This invention relates to the field of graphene preparation technology and provides a method for preparing low-defect graphene powder using a high-temperature molten salt intercalation and instantaneous expansion method. First, a graphite / molten salt composite electrode is prepared. Then, salt is intercalated into the graphite using an electrochemical intercalation method. Finally, the intercalated graphite is exfoliated into thin-layer graphene using a negative pressure high-power microwave exfoliation method or a normal pressure high-temperature quenching exfoliation method. The raw materials used in this invention are low-cost and environmentally friendly, and the production process is safe and efficient. Through the optimized combination of molten salt electro-assisted intercalation technology and the instantaneous expansion method, the prepared graphene not only has a layer count controlled at 3-5 layers and a flake size of 25-300 μm, but also exhibits few defects on the graphene flakes, providing strong technical support for promoting the high-quality development of related industries.

The invention relates to the technical field of metal composite materials, and discloses a modified graphene reinforced aluminum alloy composite material and a preparation method thereof.The preparation method comprises the steps that zirconium hydroxide is loaded on graphene oxide through a hydrothermal reaction, then zirconium oxide modified graphene oxide is obtained through high-temperature sintering treatment, then reduction treatment is conducted in the hydrogen atmosphere, and the modified graphene reinforced aluminum alloy composite material is obtained. The preparation method comprises the following steps: preparing zirconium-modified graphene, then doping a boron element by adopting an ion implantation process to obtain composite modified graphene, doping zirconium, zirconium (Zr) and aluminum to form an Al3Zr compound, so that the recrystallization process can be hindered, recrystallized grains can be refined, and the generation of an aluminum carbide phase can be inhibited; by doping the boron element, the wettability between graphene and an aluminum alloy melt is improved, the uniform dispersity of graphene in an aluminum alloy matrix can be effectively improved, meanwhile, boron serves as a grain refiner and acts together with zirconium, the grain refinement effect can be further enhanced, and therefore the strength and plasticity of the aluminum alloy are improved.

The application belongs to the field of carbon material preparation, and discloses a preparation method of self-supporting carbon nanotube and graphene hybrid material. The preparation method is as follows: two carbon sources with different carbon contents are added into a mixed solution of ethanol and water to form a suspension; the suspension is sprayed on the surface of a metal sheet, and after drying, the metal sheet is placed in a high-temperature furnace for high-temperature heating in a protective atmosphere; after the high-temperature furnace is cooled, the carbon material is taken off from the metal sheet, and then the carbon material is soaked in an acid solution, and then washed with water and dried to obtain the self-supporting carbon nanotube and graphene hybrid material. The method has the characteristics of simple operation, low cost, good product structure interconnection, and easy controllable macro preparation. The self-supporting carbon nanotube and graphene hybrid material can be used as a positive electrode carrier material of a lithium-sulfur battery.

The application relates to the field of graphene preparation, and particularly provides a method for preparing reduced graphene oxide (rGO) by visible light in an aqueous solution, which uses an LED lamp simulating the visible light section of sunlight as a light source under normal temperature and pressure, and reduces industrial-grade graphene oxide (GO) to prepare rGO in a homogeneous aqueous solution system in the presence of an organic dye molecule eosin Y (water-soluble) as a photosensitizer and triethylamine as an electron sacrificial agent. The method overcomes the shortcomings of a low yield, the need for a strong reducing agent and high pollution in a traditional preparation process, and has the advantages of simple process, easy separation, high yield, low energy consumption, low cost and no pollution, and the prepared rGO has a smooth structure, a thin thickness and a perfect graphitization degree.

The invention discloses a flexible graphene heat-conducting film and a preparation method thereof.The graphene heat-conducting film is obtained by carbonizing, graphitizing and treating a graphene oxide film, the graphene oxide film is prepared by coating and drying slurry, and the slurry comprises a solvent, graphene oxide and a carbon-based additive; the carbon-based additive comprises any one of carbon nanotubes, carbon black or carbon fibers. The carbon-based material and the graphite are introduced for in-situ / oriented oxidation, so that the oxidation process can be promoted, a novel structure in which the carbon-based material and the graphite are connected through chemical bonds is formed, oriented arrangement of molecules in the film forming process is facilitated, and the flexibility of the graphene heat-conducting film is improved; in addition, a certain proportion of carbon-based material is only introduced in the premixing stage, so that the performance of the film is improved, the processing cost is not greatly increased, the process is mature, and mass production can be realized.

The present application relates to a kind of high efficient preparation high-strength high-conductivity copper-based composite wire method, through high-purity citric acid or citrate one-step generation zero-dimensional GQDs load in two-dimensional GN surface multi-dimensional reinforcing phase, using stirring ball mill preparation kilogram-level GQDs@GN / Cu composite powder, then through pre-pressing and microwave sintering equipment preparation composite bar, finally using cold extrusion extrusion into wire material of cylindrical bar, the yield strength and tensile strength of the GQDs@GN / Cu composite wire material prepared by the method are 274MPa and 314MPa respectively, and the conductivity is as high as 95.3%IACS;The present application has short preparation time, simple process, low production cost, high yield, good reinforcing effect, and is suitable for mass production.

The application discloses a graphene dispersion liquid and a preparation method thereof, relates to the field of graphene dispersion liquid and a preparation method thereof, and aims at solving the technical problem that it is difficult to obtain a high-concentration stable graphene dispersion liquid at present. In the dispersion liquid, graphene is obtained by reduction of graphene oxide prepared by a Hummers method, and then is uniformly dispersed into N-methyl pyrrolidone under the assistance of dispersants of sodium polystyrene sulfonate and polydiallyldimethylammonium chloride. The application is used for preparing the graphene dispersion liquid.

The invention provides a preparation method of high-conductivity composite graphene, conductive ink and application thereof, and the preparation method comprises the following steps: dispersing graphene into a solvent to obtain a graphene dispersion liquid; adding a silane coupling agent with an amino group into the graphene dispersion liquid, and reacting to obtain aminated graphene; and adding a first dispersing agent into the aminated graphene, adding silver powder after uniform dispersion, and grinding to form an Ag-N coordinate bond between the silver powder and the aminated graphene, thereby obtaining the high-conductivity composite graphene. In the preparation method of the high-conductivity composite graphene provided by the invention, a silane coupling agent with an amino group is added into a graphene dispersion liquid, amination modification is completed through a condensation reaction with a hydroxyl group on the surface of the graphene, silver powder and the amino group of the graphene form an Ag-N coordinate bond, so that silver particles are completely coated with the graphene, a continuous C-Ag-C conductive network is constructed, and the high-conductivity composite graphene is obtained. According to the network, path breakpoints are reduced, interface contact resistance is reduced, charge transmission efficiency is improved, conductivity reduction after graphene compounding is effectively inhibited, and high conductivity and high heat resistance are achieved.

A food-packaging material is provided which comprises a paper substrate having a surface and a coating comprising exfoliated graphene oxide on the surface of the substrate, wherein the exfoliated graphene oxide is present at an amount of less than 1 wt %. Methods of making the food-packaging material and methods of using the food-packing material are also provided.