Highly Efficient and Stable Flexible Quantum‐Dot Light‐Emitting Diodes With Excellent Bending Resistance

ABSTRACT Flexible quantum‐dot light‐emitting diodes (F‐QLEDs) hold great promise for future wearable electronics and foldable display applications, yet their efficiency and stability remain inferior to those of their rigid counterparts. Here, we demonstrate very efficient and stable F‐QLEDs by using a PET/Ag/IZO substrate and an oxide‐layer‐free Ga 60 In 40 top electrode. Due to well‐matched energy levels and high electrical conductivity of the two electrodes, charge injection balance of F‐QLED is significantly improved. As a result, we obtained F‐QLEDs with an impressive external quantum efficiency (EQE) of 30.01% and an exceptional T 95 operational lifetime of 20 966 h at 1000 cd/m 2 , which are all the best values ever reported for F‐QLEDs. Moreover, benefiting from deformation‐tolerant capability of the liquid Ga 60 In 40 , our F‐QLEDs can also exhibit negligible efficiency degradation after bending at an ultra‐low radius of 1 mm, highlighting their excellent bending resistance. On this basis, we further fabricated high performance large‐area F‐QLEDs and double‐sided emitting F‐QLEDs (both with EQEs > 28%), demonstrating the excellent scalability of our device. We believe that the high‐performance, bendable, and scalable F‐QLEDs demonstrated here will paving the way for practical adoption of F‐QLEDs in next‐generation wearable and deformable displays.