铽离子在氯磷酸锶镧中的发光和铈对它的敏化发光

本文报道了Tb~(3+)在氯磷酸锶镧中的发光性质、浓度猝灭和Ce~(3+)对Tb~(3+)的敏化发光。实验表明在该基质中Ce~(3+)对Tb~(3+)有良好的敏化作用。文中探讨了Ce~(3+)→Tb~(3+)的能量传递机理,证明为偶极子-偶极子相互作用的共振能量传递。

The Luminescence of Tb~(3+) and Energy Transfer from Ce~(3+) to Tb~(3+) in Lanthanum Strontium Chlorophosphate

This paper reports a systematic investigation on the luminescence properties of Tb3+-activated and Ce3+-Tb3+ coactivated lanthanum strontium chlorophosphates. Samples were prepared by solid state reactions.Since photoluminescence of f-f transition emission of Tb3+ is parity prohibited. Tb3+ ion can not effectively absorb the excitation energy and its emission therefore is weak, in order to improve their luminescence properties in La1.5Sr7.0Na1.5(PO4)6Cl2 host; we have investigated the sensitization processes of Tb3+ by the coactivated Ce3+.Excitation spectra show that as La1.5Sr7.0Na1.5-(PO4)6Cl2 doped with Tb3+ is coactivated by Ce3+ there appears a strong absorption band of Cb3+, ranging over 240-340 nm, in addition to original f-f transition sharp lines of Tb3+ . That is to say there happens a strong sensitization of Tb3+ by the presence of Ce3+ ion. The emission intensity of La1.5Sr7.0Na1.5(PO4)6-Cl2:Ce0.4, Tb0.13 is 10.3 times higher than that of the corresponding phosphors singly activated by Tb3+ only.The energy transfer efficiency from Ce3+ to Tb3+ in this phosphor have been determined to be 83%. The mechanism of these energy transfer has been proved to be a process of resonance of dipole-dipole interaction.