This paper reports the development of a transparent perovskite light-emitting diode (LED) that emits near-infrared (NIR) light and can be overlaid on color displays for efficient, high-intensity NIR illumination in mobile and wearable devices. The device, with an ITO/AZO/PEIE/FAPbI3/poly-TPD/MoO3/Al/ITO/Ag/ITO architecture, achieves over 55% average transmittance in the visible spectrum, emits at 799 nm with a 5.7% total external quantum efficiency, and has a large functional area (120 mm²). This efficient, transparent NIR LED enables advanced security and sensing features in smart devices without sacrificing display space.

Chenchao Xie, Xiaofei Zhao, Evon Woan Yuann Ong, Zhi-Kuang Tan