Synergistic stabilization of perovskite quantum dots via in situ encapsulation in a thiomethyl-functionalized covalent organic framework

Encapsulating perovskite nanocrystals within porous materials, particularly covalent organic frameworks (COFs), has emerged as a viable strategy for improving their resistance to water and light-induced degradation. However, previous studies have uncovered challenges arising from the intricate post-modification processes required for incorporating functional sites, which restricted the confinement growth of perovskite nanocrystals within COF pores. Herein, we synthesize a novel thiomethyl-functionalized COF (S-COF) by reacting 2,5-bis(3-(methylthio)propyloxy) terephthalate hydrazine (S-BMTH) with benzaldehyde,4,4′,4"-(1,3,5-triazine-2,4,6-triyl)tris- (TFPT). Subsequently, a highly stable composite, MAPbBr 3 @S-COF, is prepared by in situ growth of strongly confined MAPbBr 3 quantum dots (QDs) inside the S-COF pores. Interestingly, this composite demonstrates exceptional water stability for more than 1 year, attributed to the synergistic protection provided by the S-COF and Pb(OH)Br, which shield the QDs from degradation.