采用低温燃烧法制备出Li+,Er3+共掺杂Gd2O3纳米粉体,将粉体压片成型后在1500℃真空条件下烧结10 h成功制备出Li+,Er3+共掺杂Gd2O3半透明陶瓷。对粉体和半透明陶瓷样品的晶体结构、形貌、显微结构和上转换发光特性等用XRD,TEM,SEM,FL等手段进行了表征和研究。结果表明:Li+和Er3+均匀地溶解于Gd2O3晶格之中。粉体颗粒近似球形,粒径约20~30 nm。烧结后半透明陶瓷致密度高,未见气孔存在,透光率高;在980 nm LD激发下有两个峰值波长分别为561 nm(绿光)和658 nm(红光)上转换发光带,分别对应4S3/2/2H11/2→4I15/2和4F9/2→4I15/2跃迁;Li+的掺杂抑制了Gd2O3由立方到单斜的相变,且使陶瓷样品中Er3+的上转换发光强度显著增强,红绿光之比大大提高。
Gd2O3: 1% Er,5% Li nanocrystalline powder was prepared by low temperature combustion method. The crystal structure and morphology were analyzed by means of XRD and TEM. Gd2O3: Li,Er translucent ceramics was obtained by sintering at 1500 ℃ in vacuum for 10 h. The micrograph of unpolished surface and fracture surfaces showed that the sintered Gd2O3: Li,Er ceramics with grain size at 3 ~ 4 μm had homogeneous microstructure.Under the excitation of 980 nm diode laser,very strong green and red upconversion emissions from Er3 +ions were observed. The results showed that the upconversion intensity emitted by Er3 +and the transmittance of Gd2O3: Li,Er ceramics in the visible spectral region were greatly enhanced and improved when Li+was codoped.