In Situ Synthesis of Lead-Free Halide Perovskite-COF Nanocomposites as Photocatalysts for Photoinduced Polymerization in Both Organic and Aqueous Phases

A critical challenge that hinders the application of perovskite materials is their instability toward water and light. Herein, we report lead-free bismuth halide perovskite nanocrystals encapsulated by the covalent organic frameworks (PNCs-COFs) via an in situ growth approach. The PNCs-COFs nanocomposites demonstrated good water processability that originates from the hydrophobic COFs shell. Furthermore, the COFs coating enables the formation of PNCs-COFs heterojunction, which facilitates the generation and transportation of photoinduced charge carriers. The PNCs-COFs were further applied as photocatalysts for free-radical polymerizations, photoactivating different coinitiators via both hole and electron transfer mechanisms in aqueous and organic phases. The excellent photocatalytic performance of PNCs-COFs was confirmed by high monomer conversion (up to 97.5%), diverse functional group tolerance and recyclability.