Binary host-guest strategy enables bright and efficient lead-free zero-dimensional tin halide light-emitting diodes

Lead-free tin perovskites present remarkable environmental advantages over lead-based counterparts. While substantial progress has been made with three-dimensional (3D) and 2D tin perovskite LEDs (PeLEDs), the potential of 0D tin perovskites-renowned for their exceptional optical properties and enhanced stability-remains largely unexplored for PeLEDs due to challenges in charge transport and injection. In this study, we introduce a binary host-guest strategy that overcomes these challenges, enabling the demonstration of bright and efficient 0D tin PeLEDs with orange and white light emission. By incorporating 0D tin bromide hybrid (HDAD)₃SnBr₈ into a meticulously designed binary host system, we achieved PeLEDs with a maximum brightness exceeding 7500 candela meters^-2 and an external quantum efficiency surpassing 7%. The remarkable device performance is primarily attributed to improved film morphology, enhanced charge carrier mobility, and optimized carrier balance. Furthermore, by tailoring the device structure, we realized white LEDs with a maximum luminance of 1800 candela meters^-2.