Yb^(3+)-Er^(3+)共掺杂的NaYF_4微/纳晶体的制备与上转换荧光

Preparation and Upconversion Luminescence of Yb^(3+)-Er^(3+) Codoped NaYF_4 Micro / Nanocrystals

利用水热法制备了Yb3+-Er3+共掺杂的Na YF4微纳/米晶体.氟离子与稀土离子的浓度比对微晶的相及形貌有明显的影响.低浓度比有利于形成立方相的Na YF4,样品呈球形及八面体形;高浓度比有利于形成六角相的Na YF4,样品呈六角碟状或棒状的外形.在980 nm的红外激光激发下,样品辐射红色及绿色上转换荧光,荧光的强度依赖于晶体的相结构及形貌.另外,对晶体的生长机理及上转换发光性质也进行了讨论.

Yb3 ＋-Er3 ＋codoped Na YF4 micro / nanocrystals were fabricated by hydrothermal method and the concentration ratio of F-ion to rare earth ion had obvious influence on the phase and the morphology of the micro / nanocrystals. Low concentration ratio was beneficial to the formation of cubic-structural Na YF4,and the samples morphologies presented sphericity or octahedron. High concentration ratio contributed to the formation of hexagonal-structural Na YF4,and the samples morphologies exhibited hexagonal-disk or hexagonal-rod. Under the excitation of 980 nm infrared laser,the green and red upconversion emission were obtained,and the luminescence intensities were dependent on the phase and morphology of the micro / nanocrystals. The growth and upconversion luminescence mechanism of the samples were discussed.