Room-TemperatureLasing of Sn-Based Perovskite Single-CrystalMicrosquare Plates (MSPs)

Lead-free Sn-based metal halide perovskites are low-cost, high-efficiency photoelectric materials with significant potential for micro/nanolasers, addressing the biological and environmental toxicity of lead. This study explores the lasing behavior of single-crystal CsSnBr₃ microsquare plates (MSPs) synthesized via two-step high-temperature vapor-phase epitaxy with steady-state and time-resolved photoluminescence (PL and TRPL) spectroscopies. The lasing behavior, dominated by excitons from 193 to 313 K, shows a lasing threshold of 122.5 μJ/cm² at room temperature, supported by an exciton binding energy of 63.67 meV and a near-unity power-law relationship (<i>k</i> ≈ 1) between PL intensity and pump fluence. The characteristic temperature of the lasing threshold indicates the notable thermal stability of CsSnBr₃ MSPs. Moisture is identified as a significant factor causing lasing failure in Sn-based perovskite MSPs. High crystal quality is essential for achieving lasing in micro/nanostructures based on Sn-based perovskites. These findings highlight the potential of high-temperature vapor epitaxial growth for Sn-based perovskite micro/nanolasers, paving the way for environmentally and biologically friendly optoelectronic devices.