Graphene used to make stronger, greener concrete
Graphene, the "wonder material" composed of a one-atom-thick sheet of linked carbon atoms, is the world's strongest manmade material. Now, scientists have used it to create a new type of concrete that is much stronger, water-resistant and eco-friendly than what we're used to.
To make the concrete, a team from Britain's University of Exeter devised a technique of suspending flakes of graphene in water, then mixing that water with traditional concrete ingredients such as cement and aggregate. The process is reportedly inexpensive, and compatible with modern, large-scale manufacturing requirements.
When tested, the graphene-enhanced concrete was found to have a 146-percent increase in compressive strength as compared to regular concrete, a 79.5-percent increase in flexural strength, and a decrease in water permeability of almost 400 percent. The material meets British and European standards for construction.
The increased strength and water resistance should allow structures made with the concrete to last much longer than would otherwise be possible. This means that they wouldn't have to be replaced as often, which in turn means that less concrete would have to be poured – and production of the cement used in concrete is a major source of carbon dioxide emissions.
Additionally, the inclusion of graphene in the concrete reportedly allows for a reduction of about 50 percent of other materials used, including cement. The scientists state that this factor should result in a 446 kg/tonne reduction in emitted CO2.
"Finding greener ways to build is a crucial step forward in reducing carbon emissions around the world and so help protect our environment as much as possible," says PhD student Dimitar Dimov, who led the research. "It is the first step, but a crucial step in the right direction to make a more sustainable construction industry for the future."
A paper on the research was recently published in the journal Advanced Functional Materials.
Source: University of Exeter