Mesoporous Silica Particles Integrated with All‐Inorganic CsPbBr₃ Perovskite Quantum‐Dot Nanocomposites (MP‐PQDs) with High Stability and Wide Color Gamut Used for Backlight Display

TLDR

All‑inorganic CsPbX3 perovskite quantum dots are prized for tunable, narrow‑band, high‑efficiency emission and have been employed in LEDs, yet their performance is limited by ion‑exchange‑induced spectral broadening that hinders mixing of different colors. The study aims to develop a mesoporous PQD nanocomposite that blocks ion exchange and improves stability for mixed‑color LED applications. The authors fabricated on‑chip LEDs by embedding green‑dot mesoporous silica nanocomposites with red PQDs, using silicone gel, to suppress anion exchange and enhance thermal/photo stability, and then applied the resulting PQD‑based LEDs as backlight displays. The resulting white LED achieved an NTSC color gamut of 113 % and a Rec.

Abstract

All-inorganic CsPbX3 (X=I, Br, Cl) perovskite quantum dots (PQDs) have been investigated because of their optical properties, such as tunable wavelength, narrow band, and high quantum efficiency. These features have been used in light emitting diode (LED) devices. LED on-chip fabrication uses mixed green and red quantum dots with silicone gel. However, the ion-exchange effect widens the narrow emission spectrum. Quantum dots cannot be mixed because of anion exchange. We address this issue with a mesoporous PQD nanocomposite that can prevent ion exchange and increase stability. We mixed green quantum-dot-containing mesoporous silica nanocomposites with red PQDs, which can prevent the anion-exchange effect and increase thermal and photo stability. We applied the new PQD-based LEDs for backlight displays. We also used PQDs in an on-chip LED device. Our white LED device for backlight display passed through a color filter with an NTSC value of 113 % and Rec. 2020 of 85 %.