GdBO_3中Bi~(3+)、Sm~(3+)的发光和能量传递

研究了在紫外光(UV)激发下,Bi~(3+)、Sm~(3+)单掺杂和共掺杂的GdBO_3的发射光谱、激发光谱及发光强度随组成变化的规律。发现在GdBO_3:Bi,Sm体系中,Bi~(3+)和Gd~(3+)对Sm~(3+)的发光均有敏化作用。Bi~(3+)的绝大部分能量是通过Bi~(3+)→Gd~(3+)→(Gd~(3+))_n→Sm~(3+)途径传递给Sm~(3+)的,Gd~(3+)在能量传递中起中间体作用。研究了Bi~(3+)→Sm~(3+)的能量传递机理为电偶极—电偶极相互作用的共振传递。根据406nm激发下GdBO_3:Sm体系中Sm~(3+)发光强度与浓度的关系,证明了Sm~(3+)自身浓度猝灭的机理也为电偶极—电偶极相互作用。

Luminescence and Energy Transfer of Bi~(3+) and Sm(3+) in GdBO_3

In this paper the photoluminescence of Bi3+ or Sm3+ mono-doped CdBO3 samples or Bi3+ and Sm3+ codoped GdBO3 samples and the dependence of Bi3+ and Sm3+ luminescent intensities on compositions excited by UV light have been studied. The results obtained indicate that both Bi3+ and Gd3+ can sensitize the luminescence of Sm3+. The energy transfer from Bi3+ to Sm3+ in GdBO3 occurs almost exclusively via the Gd3+ ions, that is Gd3+ plays an intermediate role in the energy transfer from Bi3+ to Sm3+ . The mechanism of the energy transfer from Bi3+ to Sm3+ has been studied too and it is concluded that it is a resonant transfer of electric dipole-dipole interaction. According to the dependence of the luminescent intensities on the concentration of Sm3+ in GdBO3: Sm under the excitation of 406nm, it has been confirmed that the mechanism of concentration selfquenching of Sm3+ is also an electric dipole-dipole interaction.