Sr2YF7:Yb,Tm纳米晶的水热制备及上转换发光性能研究

Study on hydrothermal preparation and upconversion luminescence property of Sr2YF7:Yb,Tm nanocrystal

采用温和水热法制备了七氟钇锶(Sr2YF7)∶镱(Yb),铥(Tm)纳米晶(Sr2YF7∶Yb,Tm纳米晶),并对其微结构、形貌、粒径、发光性能进行了表征。结果显示,制备的Sr2YF7∶Yb,Tm纳米晶为四方晶相结构,其形貌为类球型,平均粒径34nm;在980nm红外光激发下,其发射峰分别位于463nm、480nm、650nm处,I蓝/I红≈43,无紫外及红外发射峰出现,获得了上转换单色蓝光。依据发光强度与激发功率的关系,确定样品的蓝光与红光发射均为三光子过程,并分析了其上转换发光机制。

Sr2YF7∶Yb,Tm nanocrystals were synthesized by a mild hydrothermal method.The microstructures, morphologies,particle sizes and luminescence properties of as-prepared nanocrystals were characterized.The results showed that as-prepared nanocrystals possessed pure tetragonal structure,spherical shape and average size of about 34nm.Emissions centered at around 463,480and 650nm upon exciting with a 980nm laser diode,Iblue/Ired≈43,No UV and IR peaks were detected,and the upconversion monochromatic blue light was observed.According to the relationship between luminescence intensity and excitation power,the blue and red upconversion luminescence of as-prepared products was come from three-photon energy transfer process,the upconversion mechanism was discussed in detail.