In Situ Photocatalyzed Polymerization to Stabilize Perovskite Nanocrystals in Protic Solvents

Herein, we report a controlled radical photocatalyzed polymerization to grow protective polymer brushes from the CsPbBr3 perovskite nanocrystals (PNCs) surface via a grafting-from strategy, in which the PNCs functioned as both photocatalysts and substrates with tethered initiators for the synthesis of polymers with defined molecular weights and low polydispersity. The core–shell structured CsPbBr3–polymer nanoparticles exhibited improved colloidal stability and optical stability of the CsPbBr3 core in various polar organic solvents, water, and UV irradiation conditions, demonstrating the effective protection of PNCs by surface polymers. We posit that this surface photopolymerization technique represents a general method to incorporate different polymer compositions and structures on PNCs for surface functionalization and stabilization.