Provided are a method for preparing a vertical branched graphene comprising treating a pristine vertical graphene with an inert plasma in the absence of an introduced carbon source to develop a vertical branched graphene. The method may also include pre-treating a substrate surface with an inert plasma; depositing a pristine vertical graphene onto the substrate surface by contacting the substrate surface with a deposition plasma comprising a carbon source gas for a deposition period. Also provided are a vertical branched graphene attached to a substrate surface, the vertical branched graphene having a trunk portion extending from the substrate surface, said trunk possessing an increased degree of branching as the distance from the substrate surface increases; and a freestanding branched graphene with a proximal end and a distal end, the proximal end comprising a trunk portion, the trunk portion possessing and increased degree of branching as the distance from the proximal end increases and the distance to the distal end decreases.

This present invention disclosed a compressive graphene hydrogel and relates to a preparation method thereof. The compressive graphene hydrogel is obtained using the oxidized graphene and phytic acid as raw materials, wherein the oxidized graphene is used as the precursor. The obtained graphene hydrogel has a rich micro gap structure, a super large surface area, and high conductivity.

The present invention provides an anode material for a lithium-ion battery comprising a carbon particle having a particle size of 5 μm to 30 μm, and including defective portions on a surface of the carbon particle, the defective portions being holes or pores formed by anodic oxidation of the carbon particle.

Methods of making graphene quantums dots are provided. The methods can produce graphene quantum dots with a monodisperse size distribution. The graphene quantum dots are produced, via one-pot synthesis, from a graphene source and a strong oxidizing mixture at an elevated temperature. The strong oxidizing mixture can contain one or more permanganates and one or more oxidizing acids. Exemplary permanganates include sodium permanganate, potassium permanganate, and calcium permanganate. Exemplary oxidizing acids include nitric acid and sulfuric acid. The graphene quantum dots can have an average particle size of between about 1 nm and 20 nm and a monodisperse size distribution. For example, the size distribution can have a span about 1 or less and/or a coefficient of variance of about 0.5 or less. About 40% or more of the graphene quantum dots can have a diameter within ±5 nm of the average particle size of the graphene quantum dots.

Inter-allotropic transformations of carbon are provided using moderate conditions including alternating voltage pulses and modest temperature elevation. By controlling the pulse magnitude, small-diameter single-walled carbon nanotubes are transformed into larger-diameter single-walled carbon nanotubes, multi-walled carbon nanotubes of different morphologies, and multi-layered graphene nanoribbons.

A novel composite electrode material and a method for manufacturing the same, a composite electrode containing said composite electrode material, and a Li-based battery comprising said composite electrode are disclosed. Herein, the composite electrode material of the present invention comprises: a core, wherein a material of the core is at least one selected from the group consisting of Sn, Sb, Si, Ge, and compounds thereof; and a graphene nanowall or a graphene-like carbon nanowall; wherein the graphene nanowall or the graphene-like carbon nanowall grows on a surface of the core.

There are provided a graphene having an oxygen atom content in a predetermined range or less and a carbon/oxygen weight ratio in a specific range to show excellent electrical and thermal conductivity properties, and a barrier property, and a method and an apparatus for preparing the graphene having excellent electrical and thermal conductivity properties and a barrier property by using a subcritical-state fluid or a supercritical-state fluid. According to the method and the apparatus for preparing the graphene, impurities such as graphene oxide, and the like, may be effectively removed, such that uniformity of the graphene to be prepared may be increased, and therefore, the graphene which is highly applicable as materials throughout the industry may be mass-produced.

The present invention relates to a hierarchical composite structure comprising an open cell graphene foam or graphene-like foam, wherein the graphene foam or graphene-like foam is coated with a conductive nanoporous spongy structure and wherein at least 10% v/v of the hollow of the pores of the graphene foam or graphene-like foam is filled with the conductive nanoporous spongy structure. The invention also relates to a process for preparing a hierarchical composite structure wherein a conductive nanoporous spongy structure is electrodeposited so as to coat the open-cell graphene foam or graphene-like foam and to partially fill the hollow of the pores of the graphene foam or graphene-like foam.

The object of the present invention is to provide linked stacks of reduced graphene, in which excellent electrical property on the surface of graphene may be utilized, a method for producing the same, powder comprising the same, and film comprising the same. The object may be solved by using linked stacks of partly reduced graphene 11 comprising two or more stacks of partly reduced graphene 21 to 24 linked together, in which the stack of partly reduced graphene 21 has two or more sheets of partly reduced graphene 31 and a nanosubstance 32 held between the sheets of partly reduced graphene 31, the partly reduced graphene 31 has no carbonyl groups and has carboxyl groups 31a and hydroxyl groups 31b, and different stacks of partly reduced graphene 21 to 24 are linked to each other by an ester bond 34.

Embodiments herein relate to chemical sensors based on the non-covalent surface modification of graphene with compounds containing hydrazine or hydroxylamine functional groups for the detection of aldehyde and ketone-bearing analytes. In an embodiment, a medical device is included having a graphene varactor included a graphene layer and a self-assembled monolayer disposed on an outer surface of the graphene layer through electrostatic interactions between a partial positive charge on hydrogen atoms of one or more hydrocarbons of the self-assembled monolayer and a π-electron system of graphene. The self-assembled monolayer can include one or more compounds having one or more hydrazine groups or hydroxylamine groups, substituted hydrazine or hydroxylamine groups, or derivatives thereof. Other embodiments are also included herein.