Whitewash: Powerful Photocatalyst for Air and Water Purification and Disinfection

Breaking down harmful gases and killing bacteria and viruses

“Whitewash” is a proprietary coating with titania composite nanofiber photocatalyst with graphene. The coating allows light, harmful gas molecules, bacteria and viruses to pass through to be in contact with the nanofibres. Upon light harvest, photogenerated electrons and holes that react with oxygen and water vapor in air produce large amounts of radicals. By oxidation, the radicals convert harmful gases to harmless substances and kill bacteria/viruses.

Whitewash coated on glass tile

Whitewash is capable of purifying 300 – 400 ppb of formaldehyde

Special Features and Advantages

Allow light, gas molecules, bacteria and viruses to diffuse into the coating, and harmless converted gases to diffuse out

Durable and reusable, without consumption of the nanofibres and replenishment need

Nanomaterials all contained, causing no concern on inhaling

Washable and can be used in water to oxidize harmful organic molecules in water

Three times better in converting formaldehyde and two times better in converting nitric oxide when compared to 25-nm TiO₂

Applications

Air and water purification, e.g. in air purifiers

Glass/ceramic tile coatings for enclosed spaces such as bathrooms, kitchens, hospital wards, elevators and vehicle cabins for killing viruses and bacteria or breaking down harmful volatile organic compounds

Award & Patent

IAAM Award - International Association of Advanced Materials Sweden, (Jun 2019)

Patent No.: 8,987,706 B2 (US)

Principal Investigator

Prof. Wallace LEUNG

Department of Mechanical Engineering

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