16-year-old Samuel Burrow has found a way to scrub the world clean of toxic pollution using materials found in sunscreen and pencils! The teenager developed a white, smog-busting mixture of titanium dioxide and graphene oxide that can be applied to internal and external surfaces like paint. His solution is strong, efficient, and cheap – and it uses simple ingredients commonly found in everyday products.
Titanium dioxide has strong oxidizing properties when it is exposed to the UV radiation in sunlight. In this process, electrons are released from titanium dioxide to create free radicals, which break down any pollutants they come in contact with – including nitrogen oxides and volatile organic compounds. Although titanium dioxide building treatments (such as those in Mexico City pictured above) exist to combat air-borne pollutants, they are currently expensive and therefore difficult to scale up.
Describing the impetus for his project, Burrow wrote: “I set out to find a way of improving titanium dioxide’s properties, along with creating a cheap, easy-to-use paint-like coating that could be used by anyone, anywhere. This coating could break down pollutants anywhere where light was present. Whilst doing some separate research on graphene (because graphene is awesome), I theorised that graphene’s superior electron transport mechanisms might help prohibit electron-hole recombination in TiO2. … there seemed to be some interest in doping TiO2 with graphene, as indeed it was good at prohibiting electron-hole recombination. I realised that this would allow the coating to be used indoors — increasing its applications.” Burrow was also aware that graphene is insoluble in water, but by using water-soluble graphene oxide he could mix the two compounds into a solution. When exposed to light the titanium dioxide then breaks the graphene oxide into graphene and that can help the titanium dioxide to be more efficient.
Burrow suggests a number of applications for his discovery. In sponge form it can be used for water purification and air purification. Mixed with sand, it could help filter heavy metals from water. As a surface paint it would remove surface dirt and airborne pollutants from the environment, and as a powder it would offer “an easier distribution method for worldwide water sanitizing — simply pour the powder into the required container, leave out in the sun, and voilà — clean water.”
Samuel Burrow‘s project is one of the 15 finalists in the Google Science Fair 2014. Public voting for the finalists’ projects opens on 1 September 2014, and the the winner will be announced on 22 September, 2014. The grand prize winner receives a 10-day trip to the Galapagos Islands with National Geographic Expeditions, an incredible experience at the Virgin Galactic Spaceport and $50,000 in scholarship funding. The winner’s school also receives a $10,000 grant for computers or lab equipment and one year’s free digital access to Scientific American.
Via IFL Science