As a promising material for optoelectronic devices, cesium lead halide perovskite nanocrystals have attracted wide attention recently. However, the fast anion exchange among CsPbX₃ is a problem for applications (e.g., light emitting diode, LED) that require different colors. In this work, we report the large-scale synthesis of ultrathin cesium lead bromide (CsPbBr₃) nanoplates (NPs) of tunable edge length and thickness via a simple one-pot colloidal approach. The thickness of NPs can be precisely tuned in a monolayer level by varying the reaction kinetics. The high-quality ultrathin NPs can be prepared in large scale of 0.25 L/batch. The ultrathin CsPbBr₃ NPs emit blue light due to the strong quantum confinement effect, in contrast to the green emission of bulk CsPbBr₃. For the first time, a blue LED device has been successfully fabricated by using ultrathin CsPbBr₃ NPs as the active layer. The use of CsPbBr₃ perovskite as the emitting layer for blue LED may promote the development of next-generation LEDs and displays.

作为光电子器件的有希望的材料，卤化铯铅钙钛矿纳米晶体近来引起了广泛的关注。然而，对于需要不同颜色的应用（例如，发光二极管，LED），CsPbX ₃之间的快速阴离子交换是一个问题。在这项工作中，我们报告了通过简单的一锅式胶体方法大规模合成的边缘长度和厚度可调的超薄溴化铯铯（CsPbBr ₃）纳米板（NPs）。可以通过改变反应动力学在单层水平上精确调节NP的厚度。可以以0.25 L /批的大规模制备高质量的超薄NP。超薄CsPbBr ₃与大量CsPbBr ₃的绿色发射相反，由于强的量子限制效应，NPs发射蓝光。首次通过使用超薄CsPbBr ₃ NPs作为有源层成功制造了蓝色LED器件。将CsPbBr ₃钙钛矿用作蓝色LED的发光层可以促进下一代LED和显示器的发展。