Room-Temperature Near-Infrared Random Lasing with Tin-Based Perovskites Prepared by CVD Processing

Nontoxic metal-halide perovskite materials have triggered a revolution of emitting devices as well as solar cells. In this work, we demonstrate a lead-free γ-CsSnI₃ perovskite random lasing operated at room temperature in ambient air. The high-purity γ-CsSnI₃ films with the orthorhombic structure were grown by chemical vapor deposition (CVD). From the absorption and photoluminescence (PL) spectra, the intense PL emission at 950 nm is consistent with the γ-CsSnI₃ band-edge absorption. Moreover, the PL stability test shows the prolonged stability of CVD-grown films. With increasing excitation energy above 18 mJ/cm², the random laser with a high Q-factor (∼3000) is achieved.