Perovskite_data

In this work, we demonstrated the role of shallow energy level defect states on the emission of CH₃NH₃PbBr₃ perovskite polycrystals under laser excitation. The perovskite polycrystals were synthesized by a simple, one-step, low-cost solution self-assembled method. By adjusting the sample preparation temperature, we could manipulate the shallow energy level defect states that can be recognized through low-temperature photoluminescence measurement. Depending on the shallow energy level defect states, the sample’s emission experienced an evolution from amplified spontaneous emission to random lasing emission. Notably, the most efficient lasing threshold of 4 μJ/mm² was achieved when the sample was prepared at 333 K. The surface morphologies and other optical properties of the perovskite polycrystals were also investigated by optical microscopy, X-ray diffractometer.<br>

本研究揭示了激光激发条件下，浅能级缺陷态对甲胺铅溴（CH₃NH₃PbBr₃）钙钛矿多晶发光特性的调控作用。该钙钛矿多晶采用简便、低成本的一步溶液自组装法合成。通过调控样品制备温度，可精准调控浅能级缺陷态，该缺陷态可通过低温光致发光（low-temperature photoluminescence）测试进行辨识。基于浅能级缺陷态的差异，样品的发光行为会经历从放大自发辐射到随机激光发射的演化过程。值得注意的是，当样品于333 K下制备时，可获得4 μJ/mm²的最优激射阈值。本研究还借助光学显微镜与X射线衍射仪，对该钙钛矿多晶的表面形貌及其他光学特性开展了表征分析。