燃烧法制备NaYF_4:Er~(3+),Yb~(3+)纳米发光粉

采用低温燃烧法制备了NaYF4:Er3+,Yb3+上转换纳米发光粉。确定最佳工艺参数为:尿素用量为200%stio,烧结温度为600℃,反应时间为8min。通过X射线衍射和透射电镜分析了晶粒尺寸和粉体粒径,粒径为30～35nm。结构为六方晶相。NaYF4:Er3+,Yb3+样品对980nm附近的波长具有上转换发光效应,上转换发射光谱5个发光峰分别为380、408、522、540和658nm。拟合材料发光强度与泵浦功率之间的关系说明,380、408nm紫光发射属于三光子过程,526、540和652nm发射均属于双光子过程。

NaYF_4:Er~(3+),Yb~(3+) nano luminescence powder prepared with combustion synthesis method

NaYF4:Er3+,Yb3+ upconversion nano luminescence powder was prepared using Low-temperature Combustion Synthesis(LCS)method.The optimum technological parameters of the synthesis were determined as:urea amount of 200%stio,agglomeration temperature of 600 ℃ and reaction time of 8 min.XRD and TEM analysis shows that the crystal grain diameters of NaYF4:Er3+,Yb3+ powders are in 30 nm to 35 nm with hexagonal crystal structure.NaYF4:Er3+,Yb3+ has upconversion luminescence effect on wavelength near 900 nm,and there are five peaks in the upconversion emission spectrum,which appear at 380 nm,408 nm,522 nm,540 nm and 658 nm respectively.The relation between luminescent intensity and pump power indicates that 380 nm and 408 nm emissive purple light belongs to three-photon process;and 522 nm,540 nm and 658 nm emissions belong to two-photon process.