In-situ Reacted Multiple-Anchoring Ligands to Produce Highly Photo-Thermal Resistant CsPbI3 Quantum Dots for Display Backlights

The poor photo-thermal resistant property of halide perovskites impedes their integration into the diffusion plate for display backlights. Pure-red perovskite emitters, the dominant component for display, are vulnerable to phase transformation and their optical properties are extremely sensitive to thermal and photo-irradiation. Tremendous efforts in the past years yielded no successes in utilizing pure-red perovskite emitters for display backlights. Here, we report the first pure-red-emitting CsPbI3 quantum dots (QDs) integrated diffusion plates. An in-situ reacted multiple-anchoring ligands to synthesize the highly photo-thermal resistant QDs is developed. The resulting CsPbI3 QDs film possesses pure-red emission of 640 nm with a photoluminescence quantum efficiency (PL QY) of above 90%, high photo-resistant property under 450 nm light irradiation, nearly reversible PL QY and a stable cubic phase when suffering high temperatures up to 180 degrees C. These characteristics ensure the CsPbI3 QDs inte-grate into the polystyrene matrix through hot-melt extrusion while retaining high optical properties. The CsPbI3 and CsPbBr3-based diffusion plates cover a color area of 130% of the National Television System Committee and 97% of the Rec. 2020. Our results bring perovskites emitters a step closer to display applications.