Ultra‐Thermostability of Spatially Confined and Fully Protected Perovskite Nanocrystals by In Situ Crystallization

Abstract

Although all-inorganic perovskite materials present multiple fascinating optical properties, their poor stability undermines their potential application in the field of multi-color display. Herein, spatially confined CsPbBr₃ nanocrystals are in situ crystallized within uniform mesoporous SiO₂ nanospheres (MSNs) to regulate their size distribution, passivate their surface defects, shield them from water/oxygen, and more importantly, enhance their thermotolerance. As a result, the remnant PL intensity of the prepared spatially confined perovskite (CsPbBr₃ ) nanocrystals by in situ crystallization within uniform mesoporous SiO₂ nanospheres (SCP@MSNs) powders can be maintained over 98% of its initial value even after being immersed in harsh conditions (0.1 m HCl or 0.1 m NaOH) for 60 days. Furthermore, the prepared SCP@MSNs-PDMS film demonstrates astonishing thermostability by maintaining almost consistent room temperature PL intensities after continuous heating-cooling cycles between 200 and 25 °C, which would greatly improve its processability during potential industrial manufacturing. The fabricated LCD backlit based on SCP@MSNs covers 124% of NTSC standard and 95.6% of Rec. 2020 standard, indicating its great potential in practical display field.