Sr2.975-xCaxAlO4F：Ce0.025^3＋荧光粉的制备及发光性能研究

Luminescence Properties of Oxyfluoride Phosphor Sr_(2.975-x)Ca_xAlO_4F:Ce_(0.025)^(3+) for UV-LEDs

采用高温固相法制备了Sr2.975-xCaxAlO4F:Ce30.+025(0≤x≤1.0)发光材料,通过X射线衍射、荧光光谱测试分析,研究了Ca2+掺杂对晶体结构和发光性能的影响。XRD测试表明Ca2+的掺入并没有改变基质晶格的结构类型,且在Sr3AlO4F基质中固溶极限不超过x=0.9。荧光光谱分析表明,Ca2+掺入后能有效提高发光强度,使激发光谱宽化和发射光谱红移,在Ca2+掺入量为x=0.4时发射强度最高。考察了Sr3-xCaxAlO4F:Ce3+(x=0,x=0.4)在不同Ce3+浓度的发射强度与峰值波长,发现Ca2+掺杂量由x=0增加至x=0.4时,对应的Ce3+的猝灭浓度由0.01降低至0.0025,并且Ce3+的猝灭机制为电偶极-电偶极相互作用。

Sr2.975-xCaxAlO4F：Ce3＋0.025（0≤x≤1.0） phosphors were synthesized by the high-temperature solid-state reaction technique.Their structure and luminescence properties were investigated by X-ray diffraction and fluorescence spectrometer.The XRD data showed that the incorporation of Ca2＋ maintains the crystal structure,and the single phase limit of Ca2＋ in the phosphors was below x=0.9.The excitation and emission band shifted to a longer wavelength due to the increased crystal field strength with increasing the Ca2＋ content,and the emission intensity reached highest at x=0.4.The emission intensity and wavelength of Sr3-xCaxAlO4F：Ce3＋（x=0,0.4） phosphors as a function of Ce3＋ content were also discussed.The quenching concentration of Ce3＋ in the phosphors reduced from 0.01 to 0.0025 with increasing the Ca2＋ content from x=0 to x=0.4,and the corresponding concentration quenching mechanism is verified to be dipole-dipole interaction.