激光退火对CaSrSiO4∶Tb3+纳米荧光粉光致发光特性的改善

Improvement of Laser Annealing on Photoluminescence Characteristics of CaSrSiO4∶Tb3+ Nanophosphor

摘要:

采用高温固相反应法制备了不同掺Tb浓度的CaSrSiO₄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CaSrSiO₄基质基本一致,表明Tb离子掺入对CaSrSiO₄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CO₂激光器对CaSrSiO₄∶0.3Tb³⁺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。

Abstract:

A series of CaSrSiO₄ nanophosphors with different Tb³⁺-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 30~50nm. XRD pattern of the samples doped Tb³⁺ ions is basically consistent with that of CaSrSiO₄ matrix, indicating that Tb³⁺ dopant has little influence on the crystal structure of CaSrSiO₄ powder. Under the 285nm excitation, the intense ultraviolet, blue and green PL spectra are observed and the optimum Tb³⁺-doped concentration is 0.7%. Finally, the CaSrSiO₄∶0.3Tb³⁺ phosphor is annealed by CO₂ 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 CaSrSiO₄∶Tb³⁺ phosphor is discussed.