有机氟离子原位钝化增强CsPbBr_(3)纳米晶体发光的热稳定性

Fluoride ions in situ passivation for thermally stable CsPbBr_(3) nanocrystals

铅卤钙钛矿纳米晶体在光伏和发光器件领域拥有巨大潜力,然而热猝灭效应阻碍了材料从实验室到实际应用的转换。提出了一种在室温条件下使用有机氟化物原位钝化合成CsPbBr_(3)纳米晶体的方法,有效钝化了表面缺陷,增强了发光的热稳定性。光致发光测试表明,与未钝化的样品相比,原位钝化CsPbBr_(3)纳米晶体的室温荧光发射强度增强了约一倍;当环境温度升至100℃时,钝化样品仍然能保持70%以上的荧光强度;且在恢复常温后,钝化样品在较长时间里仍保持稳定的荧光峰值波长和发光强度。测试结果表明,提出的制备方法能有效抑制CsPbBr_(3)纳米晶体发光的热猝灭,有利于其在电致发光和下转换LED等领域的应用。

Lead halide perovskite nanocrystals have been gradually applied in the field of photovoltaic and light-emitting devices.However,the thermal quenching effect hinders the conversion process of materials to light-emitting devices such as LEDs.In this paper,a method for synthesizing CsPbBr_(3) nanocrystals using in-situ passivation of organic fluoride at room temperature is proposed,which effectively passivates surface defects and enhances the thermal stability of luminescence.Photoluminescence tests showed that the room temperature fluorescence emission intensity of in situ passivated CsPbBr_(3) nanocrystals was approximately doubled compared to pristine samples;When the ambient temperature rises to 100℃,the passivated sample can still maintain more than 70%of the photoluminescence intensity.After restoring normal temperature,the passivated sample still maintains a stable photoluminescence peak wavelength and intensity for a long time.The test results show that the preparation method proposed in this paper can effectively suppress the thermal quenching of CsPbBr_(3) nanocrystals,which is conducive to its application in electroluminescence and down conversion LEDs.