The science behind graphene
Posted by Thermene Employees on October 01, 2013. 0 Comments
We're experts on graphene here at Thermene. Today we're going to talk to you about graphene and the science behind it. What is this 'magic material' that everybody's talking about, and why is it so great for heat transfer? Let's break it down.
What exactly is graphene?
Graphene is a one-dimensional allotrope (or one of multiple physical forms) of carbon. Graphene itself has been theorized since 1962 by Hanns-Peter Boehm. However, it wasn't until 2004 that graphene was individually isolated from all the layers of graphite that it derives from. Since then, research in graphene has exploded due to its amazing properties.
What amazing properties?
Graphene, most importantly for us, has the second highest thermal conductivity in the world. The first highest is Helium II, helium supercooled to its liquid state. So effectively, graphene has the highest thermal conductivity in the world, for most purposes. Pure graphene's thermal conductivity is rated at around 5000 [W·m−1·K−1]. This is around 10 times the thermal conductivity of silver. The graphene oxide (a highly malleable, common, somewhat less pure form of graphene) that we use in Thermene is at least 80% pure.
Besides heat transfer, graphene also has amazing electron transport speed. This means that an electron can zip across the surface of a layer of graphene superfast, at 200,000 cm2·V−1·s−1. Soon enough, graphene could be powering transistors instead of silicon, as we reach its upper limits. (FYI, Thermene Graphene Thermal Paste is non-conductive).
Graphene could also be used to make thin and flexible touch substrates (screens). Currently, phones and tablets use ITO, indium tin oxide, a brittle rare-earth element that has been increasingly restricted and manipulated due to the majority of it being sourced from just one area. It is expensive and easy to break. Graphene, only absorbing around 2% of the light that passes through it, is almost transparent, very conductive, and very flexible. Soon this will be utilized on touch displays rather than ITO.
How is graphene made?
There are multiple ways to make graphene. One is by mechanical exfoliation. What that entails is basically ripping layers of graphite apart using scotch tape until you get single-layer graphene. Another much more common method is the Hummer method. It involves a cocktail of chemicals and temperatures in order to produce exfoliated graphene, which is typically dispersed in a liquid solution. Another method is through ultrasonification. This involves ripping apart layers of graphite through extreme sound waves until single and few-layer graphene sheets are left. Ultrasonification is applied to Thermene in order to maximize performance of graphene's thermal capabilities.
Where will graphene go in the future?
Within 10 years, we will start seeing the fruits of the explosion of research into graphene. We'll most likely have touch screens made out of graphene rather than the costly and brittle ITO. We'll see graphene used in a variety of electronics applications. It may replace gold on circuit boards. Within 20 years it is likely we'll see CPUs fabricated out of graphene and a combination of other materials, rather than just silicon and gold.
But you don't have to wait 20 years anymore. Today, there's Thermene. Thermene uses the amazing heat transfer capabilities of graphene already. You can buy it here now.