Efficient protection of perovskite nanoparticles in salicylic acid hollow crystal via super simple standing method

Abstract

Cesium lead bromide (CsPbBr3) perovskite nanoparticles (NPs) are widely recognized for their high potential for next-generation optoelectronic devices. However, these NPs’ conventional surface-capped organic ligands with high fluidity are frequently shed from particles during separation and purification steps, significantly reducing their stability. Therefore, a simple method to improve the strength of perovskite NPs is essential. Here, we utilized salicylic acid (SA), which acts as a ligand and protective coating of luminescent NPs, to create CsPbBr3@SA crystals using a straightforward standing technique. The CsPbBr3 NPs were perfectly encapsulated and size-limited in the SA hollow space needle-shaped crystals that retain their significant optical intensity. The fluorescence emission intensity of CsPbBr3@SA crystals without additional treatment can be maintained for six weeks under normal ambient conditions, demonstrating the SA ligand’s ability to protect CsPbBr3 NPs better. Furthermore, the green emission CsPbBr3@SA crystals are combined with K2SiF6 red phosphor and packed with a commercially available blue light emitting diode (LED) chip to fabricate a high gamut area white LED device. The highly straightforward standing method successfully enables the high-potential preparation of perovskite nanoparticles for future practical applications.

Keywords

• All-inorganic perovskite
• CsPbBr3
• Salicylic acid
• Ligand
• Standing method