Chemical-free production of graphene-reinforced inorganic matrix composites

Abstract

Provided is a simple, fast, scalable, and environmentally benign method of producing a graphene-reinforced inorganic matrix composite directly from a graphitic material, the method comprising: (a) mixing multiple particles of a graphitic material and multiple particles of an inorganic solid carrier material to form a mixture in an impacting chamber of an energy impacting apparatus; (b) operating the energy impacting apparatus with a frequency and an intensity for a length of time sufficient for peeling off graphene sheets from the graphitic material and transferring the graphene sheets to surfaces of solid inorganic material particles to produce graphene coated or graphene-embedded inorganic particles inside the impacting chamber; and (c) forming graphene-coated or graphene-embedded inorganic particles into the graphene-reinforced inorganic matrix composite. Also provided is a mass of the graphene-coated or graphene-embedded inorganic particles produced by this method.

Description

[0001] Cross references to related applications [0002] This application claims priority from U.S. Patent Application No. 14 / 998729 filed on February 9, 2016, which is incorporated herein by reference. Technical field [0003] The present invention relates to a method of producing graphene materials, and in particular to an environmentally friendly and cost-effective method of producing graphene-reinforced inorganic matrix composite materials. Background technique [0004] Single-layer graphene sheets are composed of carbon atoms occupying a two-dimensional hexagonal lattice. Multilayer graphene is a platelet composed of more than one graphene plane. Individual single-layer graphene sheets and multi-layer graphene sheet crystals are collectively referred to herein as nanographene sheet crystals (NGP) or graphene materials. NGP includes pristine graphene (basically 99% of carbon atoms), micrographene oxide (by weight <5% oxygen), graphene oxide (≥5% oxygen by weight), microfluo...

AI Technical Summary

Problems solved by technology

[0013] (1) The method requires the use of large quantities of several undesirable chemicals such as sulfuric acid, nitric acid, and potassium permanganate or sodium chlorate

[0014] (2) The chemical treatment process requires a long intercalation and oxidation time, typically 5 hours to 5 days

[0016] (4) Thermal expansion requires high temperature (typically 800°C-1,200°C) and is therefore a highly energy-consuming process

[0017] (5) Both heat- and solution-induced puffing methods require very tedious washing and purification steps

Size reduction is an energy intensive process and has a risk of explosion due to the high concentration of combustible powders

[0038] 2. Damage to graphene structure by chemical-intensive process

The removal process may create agglomerates, reducing the chance of producing evenly dispersed graphene

[0040] 4. Graphene as an input material for this method is quite expensive

The material cannot be deagglomerated through a 40 mesh screen, but it is not possible to use a suitable mesh size (625 mesh or higher) due to the coated particles clogging the mesh

[0042] 6. The use of solvent carriers on an industrial scale requires solvent recovery equipment, which will increase energy usage and production costs

[0047] 3. Air pockets (pockets) or plating solution pockets may be formed during infiltration

The process has no well-defined method to remove these bags

[0048] 4. This method is limited to substrate materials that can be plated, evaporated or sputtered

This is a chemical-intensive, energy-intensive approach that is prohibitively expensive to scale up

[0053] 2. Many organometallic compounds present significant health, safety and environmental risks compared to pure metal, glass or ceramic materials

[0054] 3. The crystalline structure of graphite was damaged using a modified Hummer method, as evidenced by widely published Raman spectroscopic data

This may adversely affect the desired electrical, thermal and mechanical properties

[0056] 5. The control of chemometrics faces significant difficulties

[0061] 3. The method is energy intensive, gas intensive and requires expensive plasma generation equipment

These inclusions adversely affect further processing

Carbon doping may adversely affect desired electrical, thermal and mechanical properties

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