Energy transfer and heat-treatment effect of photoluminescence in Eu3+-doped TbPO4 nanowires

We have successfully synthesized Eu3+-doped TbPO4 nanowires, which are orderly organized to form bundle-like structure. A thermal treatment up to 600 °C does not modify the size, shape and structure of as-synthesized sample. Due to the energy overlap between Tb3+ and Eu3+, an efficient energy transfer occurs from Tb3+ to Eu3+. The effects of Eu3+ concentration and thermal treatment on the luminescent properties of Eu3+ are investigated. The increase of Eu3+ concentration leads to the increase of the energy transfer efficiency from Tb3+ to Eu3+, but also enhances the probability of the interaction between neighboring Eu3+, which results in the concentration quenching. With the heat-treatment, the luminescence of Eu3+ presents an obvious increase, but almost no change for the luminescence of Tb3+. This difference is explained based on the TGA, DTA, and fluorescent decay dynamics analyses.