稀土激发的CaMgSi_2O_6的长余辉发光特性

Long persistent luminescent properties of CaMgSi_2O_6 doped with rare earth ions

使用固相反应法在还原气氛中制备了具有长余辉性能的CaMgSi2O6发光材料。研究了不同的共激发离子(Dy3+和Nd3+)对于材料发光性能的影响。光谱分析表明了这些磷光体在438nm处有一个宽的发射峰,这个发射峰是由Eu2+的4f65d1能级到4f7能级的跃迁所导致的,而Eu2+在透辉石中形成六配位的发光中心。获得的3种磷光体都具有长余辉发光性能。其中共掺杂Eu2+和Dy3+材料比单掺Eu2+和共掺Eu2+和Nd3+的材料具有更好的余辉强度和更长的余辉时间,其原因在于Dy3+在CaMgSi2O6晶格中形成了更深的和更高密度的陷阱。

CaMgSi_2O_6∶Eu and CaMgSi_2O_6∶Eu, RE (RE∶Dy, Nd) phosphors with long afterglow are prepared by solid state reaction. The emission of the phosphors near 438nm results from the 4f^7～4f^65d^1 transition of Eu^(2+), which was caused by the [EuO_6] emitting center formed in CaMgSi_2O_6 host. All of them show long afterglow characteristic. CaMgSi_2O_6∶Eu, Dy phosphor has the best intensity and the longest afterglow, which was due to the high trap concentration or deep trap level formed by the co-doping Dy^(3+) ions in the host.