Er3+和Ce3+/Ce4+掺杂β-BaB2O4纳米棒的制备、结构与发光性质

以Ba(NO3)2、NaBH4、Er2O3和CeO2为原料, 在十六烷基三甲基溴化铵(CTAB)表面活性剂辅助下, 采用水热法制备了β-BaB2O4 (β-BBO)纳米棒, 稀土离子Er3+单掺杂的β-BBO(β-BBO:Er3+)及Er3+和Ce3+/Ce4+共掺杂的β-BBO(β-BBO:Er3+/Ce3+/Ce4+)纳米棒. 通过X射线粉末衍射(XRD)、傅里叶变换红外(FTIR)光谱、拉曼光谱、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)和光致发光(PL)光谱分别对样品的物相、结构、形貌、成分及光致发光性质进行了表征. 研究结果表明: 微量稀土离子掺杂并不改变β-BBO的结构, 制得的纳米棒尺寸均匀, 长度在200-500 nm 之间, 直径在10-20 nm 之间; β-BBO:Er3+和β-BBO:Er3+/Ce3+/Ce4+纳米棒在400nm光激发下, 在可见光范围内都观察到中心波长为515和542 nm的绿光. 对发光机理的初步研究表明: 发光分别对应于Er3+的2H11/2→4I15/2, 4S3/2→4I15/2跃迁, 铈离子以Ce3+和Ce4+两种形式存在于体系中, Ce3+对Er3+起敏化作用, 可以显著增强β-BBO:Er3+/Ce3+/Ce4+纳米棒的发光强度, 存在Ce3+→Er3+的能量传递过程.

Preparation,Structure and Photoluminescence of Er3+ and Ce3+/Ce4+ Doped β-BaB2O4 Nanorods

β-BaB2O4 (β-BBO) nanorods, rare earth ion Er3+ doped (β-BBO:Er3+) and Er3+, Ce3+/Ce4+ co-doped (β-BBO:Er3+/Ce3+/Ce4+) nanorods were synthesized by the cetyltrimethylammoniumbromide (CTAB) assisted hydrothermal method using Ba(NO3)2, NaBH4, Er2O3, and CeO2 as raw materials. The as-prepared products were studied by X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS), and photoluminescence (PL) spectroscopy. Results indicate that the structure of the β-BBO nanorods doped with Er3+, Ce3+/Ce4+ was unchanged. The obtained nanorods have uniformdiameters of 10-20 nmand lengths of 200-500 nm. Upon excitation with 400 nm light, the doped β-BBO nanorods exhibit a strong green light emission. PL spectra indicate that the emission bands at 515 and 542 nm correspond to the 2H11/2→4I15/2 and 4S3/2→4I15/2 transitions of Er3+, respectively. In the samples, the cerium dopant exists as Ce3+ and Ce4+. Ce3+ sensitizes Er3+ and enhances the luminescence intensity of the doped nanorods remarkably and energy transfer fromCe3+→Er3+ was observed.