Intrinsically-stretchable and patternable quantum dot color conversion layers for stretchable displays in robotic skin and wearable electronics

Abstract

Stretchable displays are essential components as signal outputs in next-generation stretchable electronics, particularly for robotic skin and wearable device technologies. Intrinsically-stretchable and patternable color conversion layers (CCLs) offer practical solutions for developing full-color stretchable micro-light-emitting diode (LED) displays. However, significant challenges remain in creating stretchable and patternable CCLs without backlight leakage under mechanical deformation. Here, a novel material strategy for stretchable and patternable heavy-metal-free quantum dot (QD) CCLs, potentially useful for robotic skin and wearable electronics is presented. Through a versatile crosslinking technique, uniform and high-concentration QD loading in the elastomeric polydimethylsiloxane matrix without loss of optical properties is achieved. These CCLs demonstrate excellent color conversion capabilities with minimal backlight leakage, even under 50% tensile strain. Additionally, fine-pixel patterning process with resolutions up to 300 pixels per inch is compatible with the QD CCLs, suitable for high-resolution stretchable display applications. The integration of these CCLs with micro-LED displays is also demonstrated, showcasing their use in haptic-responsive robotic skin and wearable healthcare monitoring sensors. This study offers a promising material preparation methodology for stretchable QDs/polymer composites and highlights their potential for advancing flexible and wearable light-emitting devices.