Improved stability of all-inorganic perovskite nanocrystals in hierarchical ZSM-5 zeolites for multimodal applications

Abstract

All-inorganic perovskite quantum dots (PQDs) CsPbX3 (X = Cl and Br) are expected a new generation of promising luminescent materials with narrow-band emissions, color-tunability, and high photoluminescence quantum yields (PLQYs), but the instability towards humid environments and high temperatures restrict their practical applicability. In this work, a hierarchically structured zeolite (HSZ) of ZSM-5 (Si/Al = 50) featured micro-mesoporous cross-linked architecture was applied to encapsulate CsPbX3 PQDs through a simple thermal diffusion strategy. The luminescence performances of CsPbX3 PQDs hybridized ZSM-5 nanocomposites can be optimized in the hierarchical micro-mesoporous structures. Particularly, the CsPbBr3-HSZ ZSM-5 composite calcined at 700 °C exhibited highly water-stable luminescence performance with a full-width at half-maximum (FWHM) of 22 nm and a high photoluminescence quantum yield (PLQY, 62%), maintaining 92% of the initial emission intensity even after 100 days of immersion in water. The highly water-resistant and stable luminescent performance of the composite was attributed to the interconnected micro-mesoporous network of HSZ ZSM-5, in which micropores provide a shielding wall to isolate the CsPbBr3 PQDs from the external environment and mesopores help to promote the diffusivity of precursors towards the successful space-confinement of CsPbX3 (X = Cl and Br) PQDs. The temperature-dependent fluorescence intensity and spectral shift characteristics of CsPbBr3-HSZ ZSM-5 composite afford its capacity acting as dual-mode optical thermometers, and the water-stable latent fingerprint identification has been also demonstrated by applying the CsPbBr3-HSZ ZSM-5 nanocomposite.