三斜相GdBO3:Eu的溶胶-凝胶法制备及其格位选择激发下的光谱

用溶胶-凝胶法合成了具有三斜结构的低温相GdBO3,并与用常规的固相反应制备的类球方解石结构的样品作了比较.在高于1000℃时发生了三斜相向常规相的相变.三斜相GdBO3:Eu的荧光光谱表明阳离子在基质晶格中占据了两种格位,用A和B来分别标明.选择激发A、B格位上Eu3+,结果揭示了GdBO3结构上的变化和Eu3+之间的能量传递过程.在较高的Eu3+掺杂浓度时,两个格位均有较强的发光;在低温和低浓度条件下,得到了可分辨的相应于不同格位的发光,并观察到了两个格位间不同几率的能量相互传递.

Preparation and Site Selective Luminescence of Eu3+ in Triclinic GdBO3

Low(temperature phase of GdBO3with triclinic form was prepared by Sol(Gel process, while only pseudo(vaterite form could be obtained from the conventional solid state reaction. The triclinic form will change to pseudo(vaterite structure when being heated at higher than 1000℃. Luminescence of the triclinic GdBO3:Eu indicated the existence of two different sites of the cations in the host, which were denoted as A and B in the work. Then site selective luminescence of the sample was investigated. The influences of concentration and temperature on the luminescence properties were reported. For high Eu3+concentration, a very strong interaction took place between the dopants. Emissions from the two sites were both strong and could not be separated. At low temperature and with a low concentration, selective luminescence from the two sites was obtained. Different energy transfer rates of site A→B and B→A were also observed.