金属卤化物钙钛矿CsPbBr3具有优异的光学性能, 是作为波长转化层在液晶显示中实现全彩显示的理想材料。为了实现高效的蓝光到绿光的光转换, 采用脉冲激光沉积技术(PLD)制备CsPbBr3微米级厚膜, 通过设定激光脉冲数实现膜厚的有效调控, 并借助扫描电子显微镜(SEM)、X射线粉末衍射(XRD)、紫外-可见吸收光谱等测试手段对其形貌、晶体结构和光学性质进行分析。然后, 将CsPbBr3微米级厚膜沉积在发射波长为460 nm的蓝光发光二极管上, 并测试光转换性能。实验结果表明, 制备的CsPbBr3厚膜由(100)取向的柱状晶体组成, 且膜厚与激光脉冲数呈线性关系, 在膜厚为2.252 μm时, 在460 nm的蓝光激发下实现了完全、有效绿光的发射。此外, 在空气氛围(温度20 ℃, 湿度25%)下放置18 d, 光致发光强度无明显衰退。

The metal halide perovskite CsPbBr3 films have excellent optical properties, which is an ideal candidate material for full-color display as a wavelength conversion layer in liquid crystal display(LCD). In order to achieve efficient photoconversion from blue to green, CsPbBr3 micron-thick films have been prepared by the pulse laser deposition technique. And the morphology, structure, optical properties are investigated by means of SEM, XRD, and UV-Vis spectrum, respectively. Then the CsPbBr3 micrometer-thick film is deposited on the blue light emitting diode whose emission wavelength is 460 nm, and the performance of light conversion is measured. The results show that the obtained CsPbBr3 films are composed of highly (100)-oriented columnar crystal and the film thickness increases in proportion to the number of laser pulse. When the deposited CsPbBr3 film thickness is 2.252 μm, a pure and effective green light emission is achieved under the excitation of blue light(460 nm). In addition, the intensity of photoluminescence(PL) does not decrease significantly when the samples are placed in an air atmosphere(temperature 20 ℃, humidity 25%) for 18 days.