Graphene has some excellent strength properties, especially when it comes to its tensile strength and Young Modulus. This high strength has led to graphene being used in many composite materials.
In addition to the high strength, graphene’s other properties enable it to be used in a wide variety of applications in the construction industry.
Graphene has some excellent properties, from its high tensile strength, to its optical transparency and its high electrical conductivity. So, whilst it may seem obvious that graphene would find its place in composite materials within the construction industry, there are many more ways in which graphene (and its properties) can be utilized.
Steel and Graphene
Steel is often used within the construction industry, but graphene has a tensile strength that is more than 200 times greater than steel. However, graphene cannot currently be made into thick layers like steel, but construction companies still want to harness the power of graphene.
Many people may think that the obvious approach to graphene and steel would be as an alloy/composite, because graphene could be incorporated into steel to help improve its properties. The addition of graphene into steel not only makes the steel stronger, but it could also help to decrease the weight of the steel. However, graphene metal matrix composites are not the easiest to create, so this is more of a potential application for the future.
An area where graphene and steel are used today, is in graphene-coated steel. Rather than spend a lot of time trying to mix the specific ratio of graphene and steel, many in the construction industry prefer to use graphene’s anti-corrosion properties in the form of a coating. Graphene coatings can be used to protect steel from water, chemicals and the natural environment, and these coatings can be applied to any applications where steel is used within the construction industry. These coatings are currently being developed to increase the lifespan of steel used in construction applications.
Graphene can introduce different properties to cement. The first is an increased strength due to graphene being present in the composite matrix, and the second is creating concrete that is self-cleaning and environmentally friendly. Both graphene and graphene oxide have been used to improve the flexural strength and resistance to strength in cement. Functionalized graphene nanosheets have also been used and have been found to increase the cement strength by forming cross-links with the cement matrix.
Aside from the increased strength, the appearance and environmental performance of concrete could be improved. The thought is that the concrete could self-clean and provide a catalytic environment for the breakdown of harmful molecules into harmless compounds.
This could help to create eco-concrete that would improve the environment around where it is implemented. This could be used anywhere, but it would be most effective where the environment needs more cleaning. Whilst it could be a while before it is ready to use in the real-world, research teams are already working on implementing and tuning the environmentally beneficial properties of these graphene-concrete materials.
Graphene oxide can be used in protective paints. Graphene oxide is a functionalized form of graphene that contains oxygen-based moieties at its surface. Strictly speaking, it is not graphene, but a graphene derivative. Still, it is worth mentioning.
Graphene oxide can be incorporated into paints to form anti-corrosion paints. These graphene oxide paints form an impermeable layer above a surface and can be used on bricks (or steel frames) to protect the exterior of any building. The paints are not only resistant to air, water and the elements, but also corrosive chemicals.
In addition to corrosion resistance, graphene oxide paints can be created that don’t crack, are resistant to oil and water leaching, are scratch-resistant and paints that can be used as thermal or electrical conductors.
Whilst LED lighting might not be those most obvious construction application, the applications are within the buildings once the external construction is complete. Many bulbs are prone to overheating, which then leads to the filament breaking. The result is a short lifespan.
In these LED bulbs, the graphene helps to dissipate the heat which makes them brighter. This also means that a lower wattage graphene bulb can achieve the same amount of luminescence as a higher wattage LED bulb, but with a lower energy requirement. Additionally, the manufacturing costs of these bulbs is low, and the lifespan is much longer than conventional LED bulbs. Light bulbs that contain graphene are now commercially available.
Spray on Solar Panels
Graphene is an optically transparent material and graphene is widely used in solar cells, regardless of the form that the cell takes. The high conductivity and charge carrier mobility of graphene makes it an attractive material for photovoltaics. Researchers now believe that spray on solar panels could be used on houses. The thought is that using graphene within these solar panels will aid in potentially doubling the amount of energy converted by traditional solar panels. Spray on panels would also negate the need for cumbersome panels and expensive labor for integrating said bulky panel onto house roofs.
The optical transparency, flexible and highly conductive nature of graphene could help to create transparent and interactive (touchscreen) displays for use within buildings. It is thought that these screens could either be used across a whole window, or on the wall (like a TV), replacing the LCD and OLED displays seen today. It is also thought that transparent building “skins” could be created for use on the interior and exterior of a building to help regulate the interior atmosphere.