35308 results about "Graphene" patented technology

A process for producing nano-scaled graphene plates with each plate comprising a sheet of graphite plane or multiple sheets of graphite plane with the graphite plane comprising a two-dimensional hexagonal structure of carbon atoms. The process includes the primary steps of: (a) providing a powder of fine graphite particles comprising graphite crystallites with each crystallite comprising one sheet or normally a multiplicity of sheets of graphite plane bonded together; (b) exfoliating the graphite crystallites to form exfoliated graphite particles, which are characterized by having at least two graphite planes being either partially or fully separated from each other; and (c) subjecting the exfoliated graphite particles to a mechanical attrition treatment to further reduce at least one dimension of the particles to a nanometer scale, <100 nm, for producing the nano-scaled graphene plates.

A nano graphene-enhanced particulate for use as a lithium-ion battery anode active material, wherein the particulate is formed of a single sheet of graphene or a plurality of graphene sheets and a plurality of fine anode active material particles with a size smaller than 10 μm. The graphene sheets and the particles are mutually bonded or agglomerated into the particulate with at least a graphene sheet embracing the anode active material particles. The amount of graphene is at least 0.01% by weight and the amount of the anode active material is at least 0.1% by weight, all based on the total weight of the particulate. A lithium-ion battery having an anode containing these graphene-enhanced particulates exhibits a stable charge and discharge cycling response, a high specific capacity per unit mass, a high first-cycle efficiency, a high capacity per electrode volume, and a long cycle life.

One illustrative method disclosed herein includes forming a trench/via in a layer of insulating material, forming a graphene liner layer in at least the trench/via, forming a copper-based seed layer on the graphene liner layer, depositing a bulk copper-based material on the copper-based seed layer so as to overfill the trench/via, and performing at least one chemical mechanical polishing process to remove at least excess amounts of the bulk copper-based material and the copper-based seed layer positioned outside of the trench/via to thereby define a copper-based conductive structure with a graphene liner layer positioned between the copper-based conductive structure and the layer of insulating material.

The invention discloses a carbon/silicon/carbon nano composite structure cathode material and a preparation method thereof, belonging to the technical field of electrochemical power supply technologies. The cathode material consists of a carbon-based conductive substrate, nano silicon and a nano carbon coating layer, wherein the nano silicon is uniformly distributed on the carbon-based conductive substrate; the nano carbon coating layer is arranged on the surface of the nano silicon; the carbon-based conductive substrate is porous carbon, a carbon nanotube or graphene; the nano silicon exists in the state of nanoparticles or nano films; the weight percentage of the nano silicon in the cathode material is 10-90 percent; and the thickness of the nano carbon coating layer is 0.1-10 nanometers. The preparation method comprises the following steps of: depositing nano silicon on the carbon substrate in a reaction space in oxygen-free atmosphere by adopting a chemical vapor deposition process; and coating nano carbon on the surface of the nano silicon by adopting the chemical vapor deposition process. In the obtained carbon/silicon/carbon composite cathode material, the volume change of a silicon electrode material is controlled effectively in the charging and discharging processes, the electrode structure is kept complete, the circulation volume is large, the circulation service life is long, and the electrochemical performance is high.

A flexible, asymmetric electrochemical cell comprising: (A) A sheet of graphene paper as first electrode comprising nano graphene platelets having a platelet thickness less than 1 nm, wherein the first electrode has electrolyte-accessible pores; (B) A thin-film or paper-like first separator and electrolyte; and (C) A thin-film or paper-like second electrode which is different in composition than the first electrode; wherein the separator is sandwiched between the first and second electrode to form a flexible laminate configuration. The asymmetric supercapacitor cells with different NGP-based electrodes exhibit an exceptionally high capacitance, specific energy, and stable and long cycle life.

A lithium-ion cell comprising: (A) a cathode comprising graphene as the cathode active material having a surface area to capture and store lithium thereon and wherein said graphene cathode is meso-porous having a specific surface area greater than 100 m²/g; (B) an anode comprising an anode active material for inserting and extracting lithium, wherein the anode active material is mixed with a conductive additive and/or a resin binder to form a porous electrode structure, or coated onto a current collector in a coating or thin film form; (C) a porous separator disposed between the anode and the cathode; (D) a lithium-containing electrolyte in physical contact with the two electrodes; and (E) a lithium source disposed in at least one of the two electrodes when the cell is made. This new Li-ion cell exhibits an unprecedentedly high energy density.

An electronic device comprises a body including a single crystal region on a major surface of the body. The single crystal region has a hexagonal crystal lattice that is substantially lattice-matched to graphene, and a at least one epitaxial layer of graphene is disposed on the single crystal region. In a currently preferred embodiment, the single crystal region comprises multilayered hexagonal BN. A method of making such an electronic device comprises the steps of: (a) providing a body including a single crystal region on a major surface of the body. The single crystal region has a hexagonal crystal lattice that is substantially lattice-matched to graphene, and (b) epitaxially forming a at least one graphene layer on that region. In a currently preferred embodiment, step (a) further includes the steps of (a1) providing a single crystal substrate of graphite and (a2) epitaxially forming multilayered single crystal hexagonal BN on the substrate. The hexagonal BN layer has a surface region substantially lattice-matched to graphene, and step (b) includes epitaxially forming at least one graphene layer on the surface region of the hexagonal BN layer. Applications to FETs are described.

The invention provides a preparation method of graphene, and particularly relates to a method for preparing biomass graphene employing cellulose as a raw material. The specific preparation method comprises the following steps: 1, preparing a catalyst solution; 2, carrying out ionic coordination and high-temperature deoxidization on cellulose and a catalyst, so as to obtain a precursor; 3, carrying out thermal treatment; 4, carrying out acid treatment, and drying to obtain the graphene, wherein the prepared graphene is uniform in morphology, has a single-layer or multi-layer two-dimensional layered structure; the dimension is 0.5-2 microns; and the electrical conductivity is 25,000-45,000S/m. The preparation method is simple in preparation technology, low in cost, high in yield, high in production safety, and controllable in product dimension and physical property; industrialized production can be realized; the graphene prepared by the method can be applied to electrode materials of super capacitors and lithium ion batteries, and can also be added to resin and rubber as an additive; and the physical property of the material can be improved.

Disclosed herein is a reduced graphene oxide doped with a dopant, and a thin layer, a transparent electrode, a display device and a solar cell including the reduced graphene oxide. The reduced graphene oxide doped with a dopant includes an organic dopant and/or an inorganic dopant.

The invention discloses an electrode plate for a lithium ion battery and a manufacturing method thereof, and particularly relates to the electrode plate for the lithium ion battery taking multi-layer graphene as a conductive agent and a manufacturing method thereof. The electrode plate of the invention consists of a positive electrode or negative electrode active substance, the conductive agent and an adhesive. The method comprises the steps of: using the positive electrode or negative electrode active substance, the conductive agent and the adhesive as raw materials to obtain electrode slurry through stirring and dispersing, and then obtaining the electrode plate through coating, drying and tabletting. The conductive agent adopted by the invention has the advantages of high dispersivity, high electric conductivity, good filling effect and the like; and the method has the advantages of simplicity, low production cost and convenient popularization and application. The method can remarkably improve the electric conductivity, electrochemical capacity and enhance charge-discharge capability of electrode materials by multiples, so the method can be widely applied to the preparation of electrode plates of lithium ion batteries.

Embodiments of the present invention provide methods for fabricating graphene nanoelectronic devices with semiconductor compatible processes, which allow wafer scale fabrication of graphene nanoelectronic devices. Embodiments of the present invention also provide methods for passivating graphene nanoelectronic devices, which enable stacking of multiple graphene devices and the creation of high density graphene based circuits. Other embodiments provide methods for producing devices with graphene layer segments having multiple thicknesses.