Energy transfer in a ternary system composed of Tb(DBM)3Phen, Eu(DBM)3Phen, and poly(N-vinylcarbazole)

Abstract

A ternary system composed of Tb(DBM)3Phen (TbDP), Eu(DBM)3Phen (EuDP), and poly(N-vinylcarbazole) (PVK) was prepared with good thermal stability and the photoluminescence (PL) was studied. By comparing their emissions, it was found that energy transfer exists from PVK to lanthanide complexes in the ternary system. It also was found that the lifetime of 5D0 of Eu3+ in the ternary system is longer than that of the binary system of EuDP and PVK, but the lifetime of 5D4 of Tb3+ in the ternary system is shorter than that of the binary system of TbDP and PVK, showing evidence of energy transfer from TbDP to EuDP. Temperature-dependent PL spectra of the ternary system from 9 to 300 K further showed there is a change in energy transfer efficiencies from Tb3+ ions to Eu3+ ions at different temperature ranges, which not only is more evidence of energy transfer but also can be used as a temperature detector or a thermal-sensitive probe of a optical fiber sensor.