Highly Efficient Printed Quantum Dot Light-emitting Diodes through Ultrahigh-definition Double-layer Transfer Printing

Abstract

Highly efficient, high-definition displays with deformable form factors are essential for next-generation electronic devices. Quantum dots (QDs) offer unique advantages such as high photoluminescence quantum yield, wide color range, and high color purity. However, developing a QD patterning process for high-definition pixels and efficient QD light-emitting diodes (QLEDs) is still nascent. We present highly efficient QLEDs via ultrahigh-definition double-layer transfer printing of a QD/ZnO film. Surface engineering of viscoelastic stamps enables creating RGB pixelated patterns with 2,565 pixels per inch and monochromatic QD patterns with ~20,526 pixels per inch. This method minimizes leakage current, enhancing external quantum efficiency to 23.3%. Additionally, we demonstrate highly efficient wearable QLEDs using our technique. This study paves the way for highly efficient, full-color QD displays through transfer printing, promising next-generation display technologies.