Hokkaido University uses tungsten oxide, which is one of the "electrochromic materials" that is colored and disappears by a reversible redox reaction caused by electricity, and adopts a thin film structure to change the color and current. We have developed a new storage device that can store and read information depending on the presence or absence of.Since it can be manufactured at room temperature, it can be manufactured not only on heat-resistant glass but also on heat-sensitive plastic.It is easy to increase the area and can be manufactured at low cost.For example, it can be expected to be applied to display and memorize information such as characters and pictures on a window glass.
Tungsten oxide is a transparent and non-conducting insulator, but when it contains hydrogen electrochemically, it becomes a black metal that conducts electricity well, and conversely, when hydrogen is extracted, it returns to the original transparent insulator.This time, we focused on the change in the color of tungsten oxide, which changes from transparent to black, and the change in the ease of conducting electricity, which changes from an insulator to a metal.By setting the state of the insulator to the information "0" and the state of the metal to the information "1" in addition to the information of the color change, the information can be electrically stored and read out.
It takes about 10 seconds to display and erase information, and there is a problem that the operation of the information display device is a little slow, but in the future, the structure of the material and the device will be improved, and it will be improved in combination with touch panel technology.The electrochromic material attracted attention because it was applied as an "electronic curtain" for the Boeing 787 passenger aircraft.
