Controlling and optimizing amplified spontaneous emission based on CsPbBr3@MCM-41 molecular sieve composite

Abstract

CsPbX3 (X = Cl, Br, I) perovskites have emerged as promising candidate lasing materials due to their high optical gain, low defect state density, and high absorption coefficient. Unfortunately, they suffer from poor stability, particularly with respect to temperature, moisture, and light exposure, preventing their use in practical optoelectronic applications, such as for amplified spontaneous emission (ASE) with an ultralow laser threshold. Herein, CsPbBr3@MCM-41 molecular sieve (CMM) composites are controllably prepared by different ultrasonication and stirring treatments. In addition, different perovskite concentrations and heat-treatment conditions are also considered to demonstrate the ASE behaviors. In addition, CMM@PS (CMMP) and CMM@AB (CMMA) composites were fabricated successfully by further optimizing the mixing ratio of CMM and the polymer. More excitingly, the stability of the CMM@polymer films with respect to the external environment is greatly improved after the polymer coating. To our surprise, the CMM@ploymer thin films demonstrated ASE at room-temperature, with an ASE threshold as low as 0.136 mJ/cm2 and 0.049 mJ/cm2 for CMMA and CMMP, respectively. These results clearly shed light upon the control and optimization of CsPbBr3 perovskite composite films, paving the way for their widespread use in optoelectronic applications.