Broadband Near-infrared Luminescence Performance of Cs2 NaYCl6∶Sb,Ln Phosphors for Night Vision Imaging Systems
Cs2NaYCl6 lead-free double perovskite materials doped with Sb3+/Ln3+(Ln=Nd,Ho,Er,Tm)were suc-cessfully prepared by hydrothermal method.The structure and morphologies were studied through X-ray diffraction and scanning electron microscopy.By measuring the photoluminescence spectra,photoluminescence excitation spec-tra,and fluorescence decay curves,the luminescence and energy transfer mechanisms were discussed.The experi-mental results show that under UV excitation,Cs2NaYCl6 matrix material can generate broadband self-trapped exci-ton(STEs)luminescence after doping with trace amounts of Sb3+.Further doping with rare earth ions,under excita-tion at 320 nm,characteristic emission peaks of rare earth ions in the visible and near-infrared regions can be ob-served.It is confirmed that there is energy transfer between STEs and rare earth ions,through analysis of the emis-sion spectrum and fluorescence decay curves.Finally,the prepared fluorescent powders were directly physically mixed and coated onto a commercial 340 nm ultraviolet LED chip to prepare a wide coverage near-infrared LED,the near-infrared emission band covers 800-1 600 nm.The use of fluorescent powder conversion LEDs greatly simplifies the construction of near-infrared devices and reduces production costs.It is flexible,compact,convenient,and wide-covered in the near-infrared band,which well meets the requirements of night vision imaging system light sources.
double perovskitesrare earth ions dopingenergy transfernear-infrared LED
国家科技期刊平台
NSTL
万方数据
