A thin coating that is not visible to the human eye could make copper nearly 100 times more resistant to corrosion, creating tremendous potential for metal protection even in harsh environments, according to a finding.
Researchers from Monash (Australia) and Rice (US) Universities say their findings could mean paradigm changes in the development of anti-corrosion coatings using extremely thin graphene films.
Graphene is a microscopically thin layer of carbon atoms, already used in smartphone screens, which is engaging the attention of researchers for its tremendous potential, the journal Carbon reported.
“At this point we are almost 100 times better than untreated copper. Other people are maybe five or six times better, so it’s a pretty big jump.”
Graphene had excellent mechanical properties and great strength, said Parama Banerjee, who performed most of the studies.
Polymer coatings on metals can be scratched, compromising their protective ability, but the invisible layer of graphene is much harder to damage.
“I call it a magic material,” said Banerjee, according to a Monash statement.
Researchers applied the graphene to copper at temperatures between 800 and 900 degrees, using a technique known as chemical vapour deposition, and tested it in saline water.
“In nations like Australia, where we are surrounded by ocean, it is particularly significant that such an atomically thin coating can provide protection in that environment,” Banerjee said.
Initial experiments were confined to copper, but Banerjee said research was already under way on using the same technique with other metals.
This would open up uses for a mass of applications, from ocean-going vessels to electronics: anywhere that metal is used and at risk of corrosion.
Such a dramatic extension of metal’s useful life could mean tremendous cost savings for many industries.
R.K. Singh Raman, P. Chakraborty Banerjee, Derrek E. Lobo, Hemtej Gullapalli, Madusha Sumandasa, Ashwin Kumar, Lokesh Choudhary, Rachel Tkacz, Pulickel M. Ajayan, M.Majumder “Protecting Copper from Electrochemical Degradation by Graphene Coating ” Carbon, 2012