Luminescent Cs<sub>8</sub>PbBr<sub>6</sub> <SUP>4+</SUP> Quantum Dots Centered on the Octahedral PbBr<sub>6</sub> <SUP>4-</SUP> Cluster within Zeolite LTA: Exploring the Edge of Three-Dimensional Crystal Structure and Its Stability

Abstract

The perovskite quantum dots (QDs) of CsPbX3 (X = Cl, Br, I) exhibit exceptional photoluminescent properties, but their sensitivity to moisture and heat poses a challenge. This study presents a solvent-free synthesis approach for incorporating CsPbBr3 perovskite QDs into zeolite A. The introduction of [Cs8PbBr6](4+) perovskite QDs into the zeolite framework resulted in a highly stable configuration, maintaining its initial luminescence properties even after being underwater or exposed to heat. The structure is determined by 3-dimensional single-crystal crystallography. Each octahedral PbBr64- ion is surrounded by Cs+ ions and [Cs8PbBr6](4+) perovskite QDs being formed at the 32% of the center of a large cavity. Further, [Na12CsBr8](5+) QDs are formed at the very center of another 46% large cavities by combining Cs+, Na+, and Br- ions. The peak in the emission spectrum of Pb,Br,Cs,Na-A is similar to those of the CsPbBr3 nanocrystal, Cs4PbBr6 0-dimensional perovskite QDs, and Pb,Br,H,Cs,Na-FAU(X and Y). This work demonstrates that Pb,Br,Cs,Na-A can be produced using a simplified solvent-free synthesis procedure, which exhibits excellent stability against moisture and heat. Moreover, through a straightforward process, various quantum dots (QDs) can be incorporated into zeolite cavities to develop materials with variety photoluminescent properties.