Efficient and stretchable organic light-emitting devices based on spontaneously formed disordered wrinkles

Area of Science:

• Materials Science
• Optoelectronics
• Device Physics

Background:

• Organic light-emitting devices (OLEDs) are crucial for displays and lighting.
• Enhancing light extraction and device flexibility remains a key challenge in OLED technology.
• Current methods for achieving stretchable OLEDs often involve complex fabrication processes.

Purpose of the Study:

• To develop a facile and scalable strategy for introducing disordered wrinkles into OLEDs.
• To investigate the impact of these wrinkles on light extraction efficiency and spectral stability.
• To demonstrate the stretchability and durability of wrinkled OLEDs.

Main Methods:

• A simple, scalable method was employed to create spontaneously formed disordered wrinkles in OLEDs.
• The optical and electrical properties of wrinkled OLEDs were compared to planar devices.
• The mechanical stability of the wrinkled OLEDs under stretching was evaluated.

Main Results:

• Wrinkled OLEDs exhibited a 37% increase in luminance and an 18% increase in current efficiency compared to planar devices.
• Disordered wrinkles induced broadband light scattering, leading to angle-stable electroluminescent spectra.
• The wrinkled OLEDs demonstrated stretchability, enduring hundreds of cycles between 0% and 5% strain.

Conclusions:

• The proposed method offers a straightforward approach to enhance OLED performance and enable stretchability.
• Disordered wrinkles effectively improve light extraction and provide angle-stable emission.
• This technique paves the way for highly efficient and mechanically robust stretchable OLEDs.