How to differentiate Graphene : Production processes

09 Jun How to differentiate Graphene

Posted at 11:52h in News by Dia

How Graphene is produced

for the first time ever in 2004. This method proved that graphene was not just a theory, but a reality.

The Scotch tape method is not transferable to industrial production of graphene, but it was a stepping-stone. Several different production processes have emerged since graphene was first isolated.

Two different strategies can be applied:

1-Bottom Up:

Graphene produced from gases by Chemical Vapour Deposition (CVD)

2-Top Down:

Graphene produced from graphite by exfoliation (chemical, mechanical, oxidative)

These different processes produce various forms of graphene.

We can segment the graphene family in 2 ways:

Material Thickness

Purity

Material Thickness

Graphene is limited to 10 layers, so is less than 3 nm thick. Today, very few companies are able to produce this type of graphene.

SLG: Single Layer Graphene (1 Layer)
FLG: Few Layer Graphene (2-5 Layers)
MLG: MultiLayer Graphene (<10 Layers)
GNP: Graphite NanoPlates (<250 Layers)

For such a 2D material, thickness is a critical parameter. The thinner the material, the better the properties will be.

Purity of Graphene

Functional groups, even in low quantities, decrease its performance as an anticorrosion agent or thermal and electrical conductor.

The degree of functionalization and the level of defects depend greatly on the method of production.

Chemical Vapour Deposition Graphene (CVD)

SLG or FLG with nearly no functional groups or defects

Chemically Exfoliated Graphene

FLG or MLG with very low amount of functional groups and defects

Mechanical Exfoliated Graphene

FLG, MLG or GNP with low amount of functional groups and defects

Reduced Graphene Oxide (rGO)

SLG, FLG, MLG or GNP with functional groups and defects

Graphene Oxide (GO)

FLG, MLG or GNP with many functional groups and defects

PURITY DECREASE

Comparing Graphene

When choosing graphene, you should be careful of the quality and scalability of the graphene. It all depends on the application and how you want to use graphene.

Processes	Thickness	% Purity	Scalability
CVD	1 Layer	> 99.99%	–
Chemical exfoliation*	2-8 Layers	> 99.95%	++
Mechanical exfoliation	2-249 Layers	> 99%	++
rGO	1-249 Layers	95% < rGO < 99%	++
GO	2-249 Layers	< 80%	++