Ho3+掺杂Al2O3粉体、薄膜的结构及其发光性能

Structure and Optical Properties of Ho3+ doped Al2O3Powders and Films

摘要:

采用高能球磨法及脉冲激光沉积法(PLD)分别制备了不同浓度的Ho³⁺∶Al₂O₃纳米粉体及薄膜,利用X射线衍射仪(XRD)、分光光度计、荧光光谱仪等分析手段研究了Ho³⁺离子掺杂对Al₂O₃结构及发光性能的影响。XRD图谱显示粉体样品为六方α-Al₂O₃结构,薄膜样品为体立方γ-Al₂O₃结构。1wt%Ho3+掺杂的Al₂O₃纳米粉体在454nm、540nm附近出现由Ho3+离子能级跃迁引起的吸收峰。采用579nm的激发光源对样品进行荧光光谱检测,发现两种样品在466～492nm波段均出现F⁺心所引起的缺陷发光峰,且发光峰的强度随Ho³⁺浓度的增加而增强。

Abstract:

Ho3+: Al2O3 nano-powders and Ho³⁺: Al₂O₃ thin films were prepared by high-energy ball milling and pulsed laser deposition (PLD) repectively. The structure and optical properties were investigated by means of X-ray diffractometer（XRD）, spectrophotometer, fluorescence spectrometer. The XRD patterns show the hexagonal α-Al₂O₃ structure of nano-powders and the cubic γ-Al₂O₃ structure of films. The absorption spectra of 1wt% Ho³⁺:Al₂O₃ nano-powder show new absorption peaks at 454nm and 540nm caused by the level transition of Ho3+ ions. Using the excitation source with a wavelength of 579 nm, the photoluminescence (PL) spectra of all the samples show an emission band between 466 nm and 492 nm, which is ascribed to the absorption of F+ color center, and upon increasing Ho3+ incorporation, the intensity of those peaks are accordingly enhanced.