Tuesday, December 06, 2022

Flexible electronics get brighter: A luminescent material shines brighter by pulling together and applying an electric field

Scientists at the Daegu Gyeongbuk Institute of Science and Technology (DGIST) in Korea have created a flexible material that stretches and/or lights up brightly when an electric field is applied. The results were published in the journal Applied Physics Review and show promise for the development of bright, durable, stretchable devices for use, for example, in interactive skin displays and soft robotics.

“Our material overcomes challenges in ‘alternating-current-driven electroluminescent’ (ACEL) devices that are currently under development,” explains Soon Moon Jeong of DGIST’s Department of Energy Technology. “Current instruments do not provide as much brightness as scientists are aiming for because of issues with their design.”

Soft, light-emitting ACEL devices are made by sandwiching a light-emitting compound between two electrode layers. But for the light in the middle to reach the surface and be actually seen, it needs at least one of the electrode layers to be transparent. However, this leads to a number of issues depending on the type of material used, such as the electrode being brittle or difficult to fabricate.

Jeong and colleagues overcome this and other design issues in ACEL devices by inserting dispersive silver nanowire electrodes in parallel between two light-emitting layers made of copper-ion-doped zinc sulfide particles embedded in polydimethylsiloxane (ZnS: Cu/PDMS). Got it ZnS:Cu/PDMS has an attractive property: it generates light when deformed. This is called mechanoluminescence. Adding silver nanowire electrodes also makes the device electroluminescent. In other words, applying an electric field to it makes the material shiny. “Our device is unique in that it can produce mechano- and electroluminescence simultaneously,” Jeong says.

The design allows the use of thick light-emitting layers in contrast to previous ACEL devices which may only use layers that are thin enough to apply a strong electric field between the two electrodes. The new design overcomes this problem by inserting the electrodes as ultra-thin wires inside the light-emitting material. The thick material produces 3.8 times more electroluminescent glow than other ACEL devices.

“Our proposed structure can currently be used extensively in outdoor billboards or light-emitting banners, because of its robustness against environmental factors and its simple design,” says Jeong.

The next team wants to improve the device’s electroluminescence in response to a low electric field. To achieve this, they plan to arrange the silver nanowires in different directions, rather than parallel to the current device.

Story Source:

material provided by DGIST (Daegu Gyeongbuk Institute of Science and Technology), Note: Content can be edited for style and length.


Nation World News is the fastest emerging news website covering all the latest news, world’s top stories, science news entertainment sports cricket’s latest discoveries, new technology gadgets, politics news, and more.

Latest News

Related Stories