The big news in corrosion prevention is very, very small
Wednesday, October 16, 2013
For decades, nanotechnology has held out a great deal of promise for preventing corrosion — along with a host of other wonders — but the practical applications have always been stalled by the high cost of production. That era is about to end, thanks to some significant production improvements achieved this fall in the creation of graphene.
Graphene is an exotic material derived from lattice carbon, like graphite, but produced in sheets so thin that they’re considered to be two dimensional in a meaningful way. These nanolayers are only a few atoms thick, but are able to display extremely useful qualities, like superconduction and rust prevention.
Graphene is the most resilient material currently known, with a breaking strength 100 times stronger than steel. It is transparent and weighs almost nothing. As a conductor of heat, it outperforms all other materials without exception.
Producing it, however, has so far been a laborious process that is cost-prohibitive for common materials. In a research study from Rice University last year, scientists were able multiply the corrosion resistance of copper by 100 simply through using a graphene coating. The issue, however, was that the materials had to be heated to over 1500 degrees F to apply the graphene.
Now, a private company supported by the University of Pennsylvania has successfully tested a technique that generates synthetic graphene in bulk with roll-to-roll processing.
The National Science Foundation gave Graphene Frontiers almost $750,000 to put the project in motion, and the company announced that they should be able to produce high-quality graphene in massive sheets by 2015. The company is pioneering a technique called chemical vapor deposition (CVD) on an industrial scale to produce polycrystalline single layers of graphene.
A related development published Oct. 7 deals with "white graphene," which uses graphene’s 2-D crystalline structure but replaces the carbon with hexagonal boron nitride. The application of several nanolayers of white graphene consistently blocks oxidization for a variety of materials at temperatures up to 2000 degrees F and it can be produced in bulk rather easily. These industrial-sized sheets of white graphene no more than a few atoms thick can be manufactured through a method involving a scalable form of CVD.
Both techniques will bring corrosion protection to a new level for many different materials and industries. Jun Lou, one of the researchers who announced his results with white graphene, pointed out how significant this discovery will be:
“Everybody has been talking about these materials for electronic or photonic devices, but if this can be realized on a large scale, it’s going to cover a broad spectrum of applications.”
Lou mentioned that instead of simple electronic components, we could be looking at corrosion protection for turbines, jet engines and all kinds of equipment used in oil exploration. Deep sea submarines, mid-ocean fiber optic cables and scientific sensors deployed in extremely harsh environments could also see a new lifetime of service through corrosion protection with negligible weight and thickness.
The greatest obstacle to making these graphene coatings possible is simply launching the project and making it profitable.