Shanghai Daily news

The city plans to paint the exterior walls of World Expo pavilions with a newly invented nanotech-based coating material which acts as a "permanent air purifier," a local scientist said yesterday.
If the coating proves to be effective at air cleaning, it will be gradually used on buildings across Shanghai in order to thoroughly improve the city's air quality, scientists said.
"The coating material will become an ever-extensive permanent air purifier to improve the local environment," Shi Liyi, vice director of the Nano-Science and Technology Research Center at Shanghai University, told Shanghai Daily during an international nanotech symposium yesterday.
The coating project, which is funded by the city's Science and Technology Commission and the central government with 1.8 million yuan (US$216,800), started early this year and more than 20 researchers are taking part.
The core of the material is a titanic-oxide-based compound that comprises particles at nano-scale achieved by advanced nano-technology.
Exposed under sunlight, the substance can automatically decompose the major ingredients that cause air pollution such as formaldehyde and nitride.
Nanotechnology refers to building things with atoms and molecules to perform specific tasks at a scale of as small as 10,000th of human hair.
Because each particle of the new coating material is much smaller than a normal one, there is less space between any two such particles, making sure that the substance can very effectively decompose air pollutants if painted upon the high-rise walls, researchers said.
The material can also be applied to paving road surfaces.
Shi said that the new coating material will be used in some public buildings next year and will be eventually used to paint the World Expo pavilions.