Engineering Green- to Blue-Emitting CsPbBr Quantum Dots in Nanozeolite with High Stability for Backlight Display Application.

The performance of blue devices utilizing perovskite quantum dots (PQDs) has lagged remarkably behind that of green light-emitting diodes because of low luminescence quantum yields and poor spectral stability. Here, benefiting from the rapid and short diffusion paths within the nanosized silicalite-1 (N-Si-1) zeolite (∼40 nm) channels, CsPbBr PQDs encapsulated within N-Si-1 show a high dispersion with an ultrasmall particle size of ∼2.38 nm and a blue emission of 474 nm with a high photoluminescence quantum yield (PLQY) of 44.4%. Subsequently, the surface hydrophobization of CsPbBr-N-Si-1 using octadecyltrimethoxysilane (ODTMS) enables ultrastable blue luminescence. A white-light-emitting diode (WLED) device with CIE color coordinates (0.31, 0.28) was constructed by combining CsPbBr-M (blue), CsPbBr-N-Si-1 (green), and KSF:Mn phosphor (red) on a 365 nm chip. This work introduces a feasible strategy to modulate the emission of CsPbBr PQDs through a strong confinement effect within a hydrophobic nanozeolite matrix, offering promising applications in backlight displays.