为了利用可见光学元件实现对紫外偏振光的高性能探测,制备了 CsPbBr3纳米晶/金属线栅复合薄膜,并通过向其表面沉积Al2O3钝化层提高了薄膜荧光稳定性,获得了紫外激发下偏振敏感的钙钛矿纳米晶薄膜绿色荧光.测试结果表明,以高温热注入法获得的CsPbBr3纳米晶为立方晶系结构,形貌呈方形,尺寸约39 nm.以紫外光激发纳米晶胶体溶液可在530 nm处观测到明显的绿色荧光.以自组装方法获得的CsPbBr3纳米晶/金属线栅复合薄膜荧光发光强度随紫外激发光的偏振方向呈周期性变化,其发光偏振度约为0.54.以原子层沉积技术向此复合薄膜表面沉积Al2O3层可明显提高其荧光强度,钝化后复合薄膜的发光偏振度仍可达0.36.以上结果表明,表面钝化和引入金属线栅方法可分别优化钙钛矿纳米晶薄膜的荧光稳定性和荧光偏振度,所获得的紫外偏振敏感的CsPbBr3纳米晶复合薄膜在紫外偏振探测以及液晶显示等领域具有重要的应用价值.
In order to detect polarized ultraviolet light by visible optical elements,CsPbBr3 nanocrystal/metal wire-grid composited films were prepared.The stability of its fluorescence was improved by depositing Al2O3 passivation layer.The green fluorescence of polarization-sensitive perovskite nanocrystals film was obtained under ultraviolet exciting light.The results show that the crystal structure of the CsPbBr3 nanocrys-tals obtained by hot-injection method have a cubic crystal system structure with a square shape and an aver-age size of about 39 nm.An obvious green fluorescence at about 530 nm were observed under ultraviolet light excitation of the nanocrystal colloidal solution.The fluorescence intensity of the CsPbBr3 nanocrystal/metal wire-grid composited film obtained by self-assembly changed periodically with the polariz-ation direction of the excited light.The luminous polarization ratio is about 0.54.The fluorescence intensity of this composite film was enhanced when Al2O3 was deposited on its surface by atomic layer deposition technology.The polarization ratio of the passivated film can still reach 0.36.The above results show that the fluorescence stability and polarization of perovskite nanocrystals film can be optimized by the surface passiv-ation and the introduction of metal wire-grids,respectively.The obtained ultraviolet polarization sensitive CsPbBr3 nanocrystals composited film exhibits important application value in the fields of ultraviolet polariz-ation detection and liquid crystal display.