Following on from news out of the University at Buffalo earlier this year that a graphene varnish could significantly slow the corrosion of steel, researchers from Monash and Rice Universities have used a graphene coating to improve copper’s resistance to corrosion by nearly 100 times. The researchers say such a dramatic extension of the metal’s useful life could result in significant cost savings for a wide range of industries.
Metals are often treated with polymer coatings to help prevent corrosion, but their protective capabilities can be easily compromised by scratches. Although graphene is only one-atom thick and is invisible, not changing the appearance or feel of the metal, it is exceptionally strong and much harder to damage. This gives the material enormous potential for protecting metals even in harsh environments.
Using chemical vapor disposition, the researchers applied the graphene coating to copper at temperatures between 800 and 900 degrees Celsius (1,472 and 1,652° F). They then tested it in saline water and witnessed resistance to corrosion almost 100 times that of untreated copper.
“We have obtained one of the best improvements that have been reported so far,” said study co-author Dr Mainak Majumder. “Other people are maybe five or six times better, so it’s a pretty big jump.”
The researchers are now expanding their research to see if the technique produces similar results with other metals. They are also looking for ways to apply the coating at lower temperatures in an effort to simplify production and enhance the technique’s market potential.
The team's paper appears in the journal Carbon.
Source: Monash University
Since this layer is so thin it will inevitably be damaged by physical kontact. Will these scratches then be protected by the layer, or will the oxidation spread?