Energy-saving windows

Although windows can warm up the building automatically during the cold season, hot days can make you wish that the other windows no longer exist. Japanese scientists have created a new technique, capable of making the window seem to disappear, by turning the transparent glass window into a mirror.

The AIST National Research Institute of Advanced Industrial Science and Technology has designed and created the first-ever mirror-sized mirror glass that can be switched on and off. This glass is suitable for use in buildings, homes and cars.

A glass plate that can be turned on and off is a glass plate that can adjust its transparency or color, or in this case, to adjust its reflective properties. The two scientists Kazuki Yoshimura and Shanhu Bao have experimented with improving the properties of glass that could turn off earlier, using titanium-titanium alloy to make the film turn off. Two glass plates of size 60 x 70 cm (equivalent to 24 x 28 inches) form a window structure, and each glass plate has an internal coating of 40-nanometer magnesium-titanium alloy, along with a Palladium layer is 4 nanometers thick

The mirror turns off, changes to a colorless transparent state.(Photo: AIST)

According to two scientists Yoshimura and Bao, finding the right alloy mix is ​​essential in creating a transparent glass, saving energy, and being able to switch it on and off. Previous attempts to create removable glass panels have faced problems in their ' commercialization ', such as the cost of expensive (eg, ytrium and lanthanum) or slightly colored. yellow, not suitable for cars or obstructing sight (eg magnesium-nickel alloy)

While other types of turn-on glasses are already on the market, they tend to only achieve very small benefits in energy savings. For example, electrochromatic glass, which works by using electrical signals to change colors and absorbing light, when it reaches a high temperature, this temperature often emits infrared radiation in the room.

In contrast, the non-stop mechanism in the windows of two scientists Yoshimura and Bao, is done by changing the gas composition between the two glass panels . By inserting a small amount of hydrogen into the space between the two glass plates, the glass plate acts as a transparent window. Or alternatively, adding a small amount of hydrogen-free oxygen will form a reflective mirror.

'A small amount of hydrogen and oxygen used during the toggle process can be easily generated by splitting water,' the scientists said. 'The thin film has proved its great turn-off properties . the change between the two states is very impressive.'

By applying this switchable glass plate to windows in homes, offices and buses, scientists estimate that the need for reduced air conditioning can help save energy. to over 30%. Scientists at the AIST institute are currently studying to increase the strength of this glass plate that has the ability to turn on and off to the maximum level and overcome the damage caused by continuous switching on and off. In addition, since magnesium-titanium alloy can be used for other transparent materials besides glass, there may be more applications to be discovered in the future.

Thanh Van