Linearly Manipulating Color Emission via Anion Exchange Technology for High Performance of Amplified Spontaneous Emission of Perovskites.

The most attractive advantages of all-inorganic cesium lead halide perovskites (LHPs) are their optical gain over broad spectral ranges through the visible spectrum, and so are well suited to use in tunable lasers or broadband amplifiers. Most reported anion exchange reactions face a challenge to achieve the desired halogen-variable perovskites due to rapid and uncontrollable reaction and difficulty to synthesize directly. In this study, we demonstrate a simple vapor/solid anion exchange strategy for controlling the reaction process and realizing a wide range tuning of band gap and amplified spontaneous emission (ASE) wavelength, which exhibits a temperature dependent anion exchange rate. By optimizing the reaction temperature at 90°C, the ASE wavelength can be linearly manipulated by just controlling the reaction time. A clear quantitative relationship between ASE peak position and reaction time was achieved. Compared with the CsPbClBr 2 film obtained via liquid phase anion exchange method, our fabricated perovskite films obtained by vapor/solid anion exchange technology exhibit superior film quality and enhanced ASE performance. This work may have applications in the future using facile and controllable techniques to develop high quality full-color visible lasers. This article is protected by copyright. All rights reserved.