Researchers from Graphene Flagship in Cambridge, along with teams from Italy and Israel, have created an innovative graphene composite. Working in collaboration, they’ve discovered a new way to reduce the amount of nitrogen oxides (NOx) that escapes into the atmosphere.
They have developed a composite graphene-titania photocatalyst that in initial testing can degrade up to 70% more atmospheric NOx than standard titania nanoparticles.
Marco Goisis is a research coordinator at Italcementi, in Italy, he said:
We answered the Flagship’s call and decided to couple graphene to the most-used photocatalyst, titania, to boost the photocatalytic action. Photocatalysis is one of the most powerful ways we have to de-pollute the environment because the process does not consume the photocatalysts. It is a reaction activated by solar light. This process offers much more powerful photodegradation properties than bare titania alone.
The process they used for creating the graphene is a liquid-phase exfoliation of graphite. By using only water and atmospheric pressure, in the presence of nanoparticles, they were able to create a new graphene-titania nanocomposite that can be coated on the surface of materials with the ability to passively remove pollutants from the air. The coating can be applied to concrete walls of buildings or streets and harmless photodegradation can be manually cleaned or washed off by wind and rain.
The team tested the photocatalyst to measure the photodegradation effects.
“Coupling graphene to titania gave us excellent results in powder form – and it could be applied to different materials, of which concrete is a good example for widespread use, helping us to achieve a healthier environment. It is low-maintenance and environmentally friendly, as it just requires the sun’s energy and no other input,” Goisis says.
They still face challenges before this can be used for commercial use. This process is not cheap, so this is one of the challenges they are trying to solve. The team is also looking to test this method long term to see how it holds up to the elements. However, this is an exciting discovery and could lead to cleaner air quality for all.
