A natural graphite-based modified composite material, a preparation method therefor, and a lithium ion battery comprising the modified composite material. The natural graphite-based modified composite material comprises natural graphite and non-graphitized carbon coated on the inner and outer surfaces of the natural graphite. The preparation method comprises: (1) subjecting spherical natural graphite to isotropic treatment; (2) performing granularity control and shaping treatment; (3) subjecting the inner surface and the outer surface of the material obtained in step (2) to simultaneous modification; and (4) performing carbonization, so as to obtain a natural graphite-based modified composite material.

A water-based graphene dispersion is made by shear stabilization. The method of preparing the water-based graphene dispersion using shear stabilization includes adding a composition containing a graphene powder, a super wetter surfactant and a water dispersible rheology agent into water to form an aqueous mixture; and shearing the aqueous mixture under high pressures to break down the thick layers of the graphene powder to thin layers of graphene platelet particles and to form the water-based graphene dispersion with the graphene platelet particles dispersed in the water-based graphene dispersion. The water-based graphene dispersion is stable without visible phase separation after storage at room temperature for at least one year or even more than one year.

The invention described herein provides a dry graphene powder composition comprising pristine graphene flakes, wherein the pristine graphene flakes are non-covalently functionalised with polymeric amphiphilic molecules and wherein the dry graphene powder composition is capable of forming a stable homogeneous dispersion in aqueous or alcoholic media, in the absence of free dispersants or stabilizers, as well as methods for producing same, and the use thereof in graphene inks, for 2D and 3D printing, for production of flexible circuits, electrodes, electrocatalysts, for fabrication of nanocomposites and for wet-spinning of pristine graphene fibers.

A material of porous graphene nanowires with a pore-rich structure is formed by synthesis of catalyst nanowires for porous graphene nanowires, chemical vapor deposition of a carbon source on the catalysts to grow graphene, removal of residual catalyst, and formation of the porous graphene nanowires. The porous graphene nanowires can be used as an electrochemical energy storage material, carriers of catalysts, a conductive material, an adsorption material, a desorption material, or the like.

Several variations of synthetic carbon materials are disclosed. The materials can assume a variety of properties, including high electrical conductivity. The materials also can have favorable structural and mechanical properties. They can form gas impenetrable barriers, form insulating structures, and can have unique optical properties.

A method for preparing a graphite film includes steps of preparing a carbonized frame carbonized at a temperature Ta, and an aromatic polyimide film or a carbonized film of the aromatic polyimide film carbonized at a temperature Tb, assembling the carbonized frame and the aromatic polyimide film or the carbonized film of the aromatic polyimide film into an intermediary body, carbonizing the intermediary body 1 at a temperature Td to produce a carbonized intermediary body, and graphitizing the carbonized intermediary body to produce the graphite film. The temperature Ta is larger than the temperature Tb and the temperature Tb is smaller than the temperature Td. The graphite film has a surface roughness expressed as an arithmetic mean height Sa of less than 18 nm, a thickness of 5 nm or more and less than 10 μm, and an area of 1.0 cm.sup.2 or more and less than 500 cm.sup.2.

Disclosed herein are graphene coatings characterized by a porous, three-dimensional, spherical structure having a hollow core, along with methods for forming such graphene coatings on glasses, glass-ceramics, ceramics, and crystalline materials. Such coatings can be further coated with organic or inorganic layers and are useful in chemical and electronic applications.

A battery system comprising: an anode composed of a non-toxic biocompatible metal; a first printable carbon-based current collector comprising biocompatible multiple few layer graphene (FLG) sheets in electrical contact with and extending from the anode; a three-dimensional (3D) hierarchical mesoporous carbon-based cathode including an open porous structure configured to catalyze an active material via gas diffusion; a polymer-based barrier film deposited on the 3D hierarchical mesoporous carbon-based cathode, the polymer-based barrier film configured to prevent oxygen from entering the open porous structure while deposited on the 3D hierarchical mesoporous carbon-based cathode; a second printable carbon-based current collector comprising biocompatible multiple few layer graphene (FLG) sheets in electrical contact with and extending from the cathode; and an electrolyte layer disposed between the anode and the cathode, the electrolyte layer configured to activate the battery system when released into one or both of the anode and the cathode.

A conductive material, and a method for preparing the same are provided. The conductive material has a structure where a plurality of graphene sheets are interconnected, wherein an oxygen content is 1 wt % or higher based on the total weight of the conductive material, and a D/G peak ratio is 2.0 or less when the Raman spectrum is measured.

Disclosed herein are graphene coatings characterized by a porous, three-dimensional, spherical structure having a hollow core, along with methods for forming such graphene coatings on glasses, glass-ceramics, ceramics, and crystalline materials. Such coatings can be further coated with organic or inorganic layers and are useful in chemical and electronic applications.