Poly(catecholamine) Coated CsPbBr3 Perovskite Microlasers: Lasing in Water and Biofunctionalization

Lead halide perovskite (LHP) is a promising material for various optoelectronic applications. Surface coating on particles is a common strategy to improve their functionality and environmental stability, but LHP is not amenable to most coating chemistries because of its intrinsic weakness against polar solvents. Here, a novel method of synthesizing LHP microlasers in a super-saturated polar solvent using sonochemistry and applying various functional coatings on individual microlasers in situ is described. Cesium lead bromine perovskite (CsPbBr3) microcrystals, capped with organic poly-norepinephrine (pNE) layers, are synthesized. The catechol group of pNE coordinates to bromine-deficient lead atoms, forming a defect-passivating and diffusion-blocking shell. The pNE layer enhances the material lifetime of CsPbBr3 in water by 2000-fold, enabling bright luminescence and lasing from single microcrystals in water. Furthermore, the pNE shell permits biofunctionalization with proteins, small molecules, and lipid bilayers. Luminescence from CsPbBr3 microcrystals is sustained in water over 1 h and observed in live cells. The functionalization method may enable new applications of LHP laser particles in water-rich environments.

Automated summary

This study introduces a novel method of synthesizing LHP microlasers and applying functional coatings for applications in water-rich environments. The research demonstrates that organic pNE layers play a key role in enhancing the material lifetime of CsPbBr3 and enable bright luminescence and lasing in water.