Facile Fabrication of Stretchable Touch Responsive Perovskite Light-Emitting Diodes through Using Robust Stretchable Composite Electrodes.

Perovskite light-emitting diode (PeLED) has been vigorously developed in recent years. As it has demonstrated well performance on the rigid substrates, the next important direction of PeLED is their integration with stretchable components to realize stretchable, responsive device. Here, we describe a facile fabrication of stretchable perovskite light-emissive touch-responsive devices (PeLETDs) through utilizing highly transparent and conductive polyurethane/silver nanowires (PU/AgNWs) as the electrode. Meanwhile, a stretchable tri-composite perovskite emissive layer was developed by blending a small amount of poly(ethylene oxide) (PEO) and polyvinylpyrrolidone (PVP) with CsPbBr3. Additionally, a thin PVP layer was introduced at the bottom side of the emissive layer. On one hand, it can further improve the morphology of the emissive layer; on the other hand, it can serve as an electron-injection barrier to reduce the high non-radiative recombination at the corresponding interface. Further, to fulfill the responsive function of the fabricated PeLEDs, a poly(ethylene terephthalate) (PET) spacer with a 100-μm thickness was inserted between the top electrode and the emissive layer. A stretchable PeLETD is finally demonstrated to possess a low turn-on voltage of 2 V with a brightness of 380.5 cd m-2 at 7.5 V, and can sustain 30% uniaxial strain with a small luminance variation of 24%. More intriguingly, our stretchable PeLETD exhibited high stability, which could be well touch responsibility, where the luminance is on/off switched for 300 cycles by the repeated pressure.