激光退火对CaSrSiO_(4)∶Tb^(3+)纳米荧光粉光致发光特性的改善

Improvement of Laser Annealing on Photoluminescence Characteristics of CaSrSiO_(4)∶Tb^(3+) Nanophosphor

采用高温固相反应法制备了不同掺Tb浓度的CaSrSiO_(4)纳米荧光粉。TEM照片显示粉末颗粒为球状,直径30~50nm。XRD主要衍射峰与CaSrSiO_(4)基质基本一致,表明Tb离子掺入对CaSrSiO_(4)晶体结构影响较小。285nm紫外光激发下,观测到强的紫外、蓝光和绿光等光谱,优化掺Tb浓度为0.7%。最后用CO_(2)激光器对CaSrSiO_(4)∶0.3Tb^(3+)荧光粉进行退火,发现光谱增强50%以上。同时讨论了退火工艺参数对荧光粉光致发光特性的影响。

A series of CaSrSiO_(4) nanophosphors with different Tb^(3+)-doped concentrations have been prepared by high-temperature solid-state reaction method.SEM image shows that the powder particles show a shape of ball and a diameter of about 30~50 nm.XRD pattern of the samples doped Tb^(3+)ions is basically consistent with that of CaSrSiO_(4) matrix,indicating that Tb^(3+)dopant has little influence on the crystal structure of CaSrSiO_(4) powder.Under the 285 nm excitation,the intense ultraviolet,blue and green PL spectra are observed and the optimum Tb^(3+)-doped concentration is 0.7%.Finally,the CaSrSiO_(4)∶0.3 Tb^(3+)phosphor is annealed by CO_(2) laser and its spectral intensity is enhanced by more than 50%.At the same time,the effect of annealing process parameters on PL characteristics of CaSrSiO_(4)∶Tb^(3+)phosphor is discussed.