Thursday, 6 March 2008

Toshiba Materials Develops World's First Visible Light

Toshiba Materials announced this week the world's first photocatalyst that delivers effective anti-bacterial and deodorizing performance under low level illuminance (below 200 lux*1) such as indoor light, and which also achieves over 30 times the gas-decomposition efficiency of current titania-based photocatalysts.

Commercialized photocatalysts are primarily used for their anti-fouling properties, and are coated on the external walls and windows of buildings to provide a layer of added protection.
They are usually based on titania (titanium dioxide), which reacts to ultra-violet light. As a result, their use has been limited to outside applications.

Attempts to develop new titania-based photocatalysts that react to visible light and that can be used indoors have proved unsuccessful, as titania-based photocatalysts only produce notable results in visible light when illuminance is in the region of 6,000 lux. A typical living room has an illuminance level in the region of 200 lux.

Toshiba Materials has now developed a non-titania photocatalyst that reacts to visible light at an illuminance as low as 200 lux. This breakthrough will allow the use of photocatalysts to be extended to indoors, and to many new applications.

The company said it achieved the new photocatalyst through nano-scale fabrication of particles with a diameter of less than 100nm*2, optimization of the surface of the particles, and an activation process that optimizes the nano-structure of the photocatalyst and enhances its range of light absorbance.

As a result, the photocatalyst can be applied to shaded rooms and ceilings, and to corners of rooms that receive little direct sunlight, and still achieve effective anti-bacterial and deodorizing performance.

The high level performance of the new photocatalyst will allow application on internal surfaces, and can even be extended to include furniture and home appliances and medical applications.

Toshiba Materials will cooperate with major companies working in such areas as interior decoration, environmental control in schools and hospitals, deodorants, and home appliances, to promote practical use.

The overall market for photocatalysts is expected to grow to 60 billion yen by 2011.

Within that, Toshiba Materials said it will seek to grow net sales of its visible light photocatalyst to 10 billion yen.