Enhanced amplified spontaneous emission of flexible MAPbBr3 perovskite films with excellent mechanical reliability

Halide perovskites have been proven to have enormous potential for further flexible optoelectronic devices. However, the repeated mechanical bending and tolerance to moisture corrosion remain a critical challenge for flexible perovskite devices. Solution chemistry of a precursor is the basis for the preparation of high-quality perovskite films and can significantly enhance the lasing performance and humidity stability of perovskites. Herein, from the perspective of solvent engineering, two ionic liquids (ILs) of methylammonium acetate (MAAc) and methylammonium propionate (MAP) were introduced to prepare high-quality MAPbBr3 perovskite films. The as-prepared MAPbBr3 perovskite films exhibit not only enhanced amplified spontaneous emission (ASE) performance but also the excellent mechanical reliability even in a humid environment. Especially, the MAAc-based MAPbBr3 perovskite film possesses the morphology optimization, defect passivation, simultaneous improvements in ASE, and bending durability due to the stronger coordination capacity and reactivity between MAAc and Pb2+. Our work provides an effective strategy for flexible perovskite based photonic devices fueled by the remarkable mechanical reliability.