摘要
Perovskite light-emitting diodes (LEDs) have achieved external quantum efficiencies (EQEs) above 20% in the red, green, and blue spectral regions, yet their efficiency rapidly declines as the bandgap widens for shorter-wavelength emission. This limitation hampers the development of high-bandgap perovskite LEDs, including ultraviolet (UV) devices. Here, we report efficiency enhancement in violet-emitting perovskite quantum dot LEDs through ZnCl2 post-treatment doping as a step toward future UV LED technologies. ZnCl2 doping significantly improves optoelectronic performance, increasing the EQE from 0.38% to 0.90%, raising the maximum luminance from 95.29 to 156.39 cd/m2, and reducing the turn-on voltage from 3.88 to 3.65 V. These results indicate that ZnCl2 post-treatment effectively enhances carrier transport and overall device performance, offering a promising strategy to enable efficient high-bandgap perovskite LEDs.