All-inorganic perovskite quantum dots (AIP QDs) have triggered extensive interest due to their unique optical properties in very recent years. The downconversion (DC) and upconversion (UC) luminescence corresponding to Stokes and anti-Stokes effect are two reverse luminescence phenomena. However, it is seldom to realize these two-reverse luminescence effects in individual QDs simultaneously. Therefore, it is highly desirable to develop comprehensive optical characteristics in order to achieve the multifunction in AIP QDs. Here, colloidal CsPbBr₃ perovskite QDs were successfully synthesized by a convenient solution approach. The as-prepared colloidal CsPbBr₃ QDs possess highly crystallinity. The DC and UC luminescence properties were studied under ultraviolet (UV) light and infrared (IR) lasers. We have demonstrated that CsPbBr₃ QDs exhibited both strong green emission from DC and UC characteristic. In addition, a light-emitting diode device was demonstrated with our CsPbBr₃ QDs, showing high-purity green feature. This work reveals the photoluminescence of AIP CsPbBr₃ QDs excited by different excitation sources, promoting their multi-functional applications for downconversion and upconversion luminescence.

近年来，全无机钙钛矿量子点（AIP QD）由于其独特的光学性能而引起了广泛的关注。与斯托克斯效应和反斯托克斯效应相对应的下转换（DC）和上转换（UC）发光是两种反向发光现象。但是，很少会在单个QD中同时实现这些两个反向发光效果。因此，迫切需要开发出全面的光学特性以实现AIP QD的多功能性。在这里，胶体CsPbBr ₃钙钛矿量子点通过便利的解决方法成功地合成。制备的胶体CsPbBr ₃QD具有高度结晶性。在紫外线（UV）和红外线（IR）激光下研究了DC和UC的发光特性。我们已经证明，CsPbBr ₃ QDs从DC和UC特性均显示出强绿色发射。此外，我们的CsPbBr ₃ QD演示了一种发光二极管器件，具有高纯度的绿色特性。这项工作揭示了由不同激发源激发的AIP CsPbBr ₃ QD的光致发光，促进了其在下转换和上转换发光中的多功能应用。