Enhancing the Optical Properties and Stability of CsPbBr₃ Quantum Dots through Ligand Modification, Encapsulation,...

Reducing the detachment of ligands on all-inorganic cesium lead bromide perovskite quantum dots (CsPbBr₃ PQDs) presents a significant challenge to their practical applications, despite their remarkable optoelectronic properties. Herein, a novel strategy was introduced to passivate the surface defects of CsPbBr₃ PQDs by employing short-chain surface ligands and functional groups within a polymer matrix to enhance their processability. Guanidinopropanoic acid (GPA) was employed as a coligand alongside oleic acid and oleylamine to synthesize CsPbBr₃-GPA PQDs via the hot injection method. A nitrogen-containing, superhydrophobic mesoporous polymer, poly(divinylbenzene)-vinylimidazole (PDVB-Vim), was utilized as an innovative encapsulation material for CsPbBr₃ PQDs, resulting in the formation of the CsPbBr₃-GPA@PDVB-Vim composite. CsPbBr₃-GPA PQDs were successfully protected from unfavorable external stimulation, such as water and UV light, by the protective PDVB-Vim. CsPbBr₃-GPA@PDVB-Vim retains over 76% of its initial photoluminescence intensity after 31 days in water and 68% after 96 h of continuous exposure to 365 nm UV irradiation at an intensity of 15 mW·cm^-2. The screen printing of CsPbBr₃-GPA@PDVB-Vim with methyl methacrylate, butyl methacrylate, and styrene demonstrates its potential as a stable light conversion material for wearable devices. This breakthrough may pave the way for further advancements in using CsPbBr₃-GPA@PDVB-Vim as a highly stable photoluminescent material for wearable luminescent textiles and light conversion applications.