The amazing properties of Graphene include exceptionally high tensile strength (100 times stronger than steel), excellent thermal and electrical conductivity and the thinnest 2D material in existence. Graphene is then suitable for a wide spectrum of next-generation applications including as the fundamental building blocks of Carbon Nanotubes (CNTs).
High Pressure Homogenization is becoming widely used as an effective mechanical Graphene exfoliation technique.
Graphene exfoliation methods
Generally, two different strategies can be applied:
1. Top Down: Graphene produced from graphite by exfoliation - using any of the following methods - mechanical (including our technology), chemcial and oxidative. Mechanical methods also include (ultra) sonication and high shear mixing.
Bottom Up: Graphene produced from gases by Chemical Vapour Deposition (CVD).
There is also the approach that involves the unzipping of carbon nanotubes (CNTs) to obtain graphene nanoribbons / nano-strips.
High Pressure Homogenizers - Graphene production - Liquid-phase exfoliation
Our leading high pressure technology provides one of the most promising methods to address the challenges listed below for during Graphene exfoliation.
Pilot - Production scale Homogenizer
Challenges of Graphene production
Low graphene yields.
Scaling-up graphene production to industrial levels without any negative effect on its properties including electrical conductivity and strength.
The quality of graphene produced.
Scalability
Perhaps one of its most promising features of our high pressure systems is their ability to scale-up to higher graphene production levels and to do so with repeatable results.
One example is the production of large volumes of Graphene conductive ink from a flake graphite solution which is pumped in to the homogenizer processing chamber where it undergoes high energy / high-shear. The end product is a highly concentrated graphene suspension.
Increasing Graphene yields
When processing Flake Graphite the yields of Graphene are typically small, even as low as 1%. Obviously this is inefficient and so increases production costs and time.
The high shear process of HPH can increase Graphene yields by a high margin, and this percentage can be increased in each additional cycle through the Homogenizer - more below.
Improving Graphene quality
The quality / purity of Graphene produced can be determined by multiple factors, not only the Graphite exfoliation method used.
Pristine Graphene can be achieved when using high pressure technology, like ours, when using high-quality Flake Graphite as the raw material. HPH can provide milder exfoliation conditions that may help to decrease the formation of defects.
Another benefits of using our high pressure technology is that by adjusting the processing time and pressure the thickness distribution and Graphene 'sheet' area can be controlled.
Lowering Graphene Production costs
HPH can utilize a cheap and abundant source - Flake Graphite - as the raw material for Graphene production.
Improved scalability, processability and reproducibility of results.
Has the ability for continuous processing to maximise the Graphene yield and options for different types of HPH processing components.
The diagram below show how the solution is recycled from the outlet reservoir back in to the inlet reservoir to start another cycle - this can increase yield and also lower production costs.
During each cycle the graphite flakes, which can move within the liquid, can be exfoliated repeatedly whilst under very high pressure. The Graphene particles produced can be 1 to 2 micron in lateral size and with a uniform product.
HPH is proving to be a cost-effective and efficient exfoliation technique.
Please contact us now to discuss your Graphne production requirements.
Production Scale
Laboratory Homogenizer
Pilot - smaller scale production
