Highly stable and controllable lasing actions from PVDF encapsulated CsPbBr3 perovskite microcrystals

Abstract

Halide perovskite (HP)-based optoelectronics, particularly lasers, have attracted considerable attention thanks to their outstanding low threshold and tunable bandgaps. Surface coating is one of the most common strategies for significantly improving the phase stability and suppressing the leakage of lead, but HPs are vulnerable to most coating chemistries because of their natural weakness against polar solvents. Herein, polyvinylidene fluoride (PVDF) encapsulated CsPbBr₃ microcrystals are synthesized by using an in situ growing method. Subsequently, a Fabry–Pérot (F–P) CsPbBr₃ micro-laser with a low threshold (14.4 μJ cm⁻²), a well-controlled mode spacing, and even ultra-high long-term stability is experimentally realized at room temperature. In addition, the optical performance of the PVDF wrapped CsPbBr₃ microcrystals is sustained in water for 35 days. This work enables a convenient and effective route to controllably fabricate perovskite microlasers with long-term stability.