Room temperature synthesis of stable silica-coated CsPbBr3 quantum dots for amplified spontaneous emission

All-inorganic cesium lead bromide(CsPbBr) perovskite quantum dots(QDs) with excellent optical properties have been regarded as good gain materials for amplified spontaneous emission(ASE). However, the poor stability as the results of the high sensitivity to heat and moisture limits their further applications. Here, we report a facile one-pot approach to synthesize CsPbBr@SiOQDs at room temperature. Due to the effective defects passivation using SiO, as-prepared CsPbBr@SiOQDs present an enhanced photoluminescence quantum yield(PLQY) and chemical stability. The PLQY of CsPbBr@SiOQDs reaches 71.6% which is higher than 46%in pure CsPbBrQDs. The PL intensity of CsPbBr@SiOQDs maintains 84% while remaining 24% in pure CsPbBrafter 80 min heating at 60°C. The ASE performance of the films is also studied under a two-photonpumped laser. Compared with the films using pure CsPbBrQDs, those with as-prepared CsPbBr@SiOQDs exhibit a reduced threshold of ASE. The work suggests that room-temperature-synthesized SiO-coated perovskites QDs are promising candidates for laser devices.