Structural and luminescence properties of Eu-doped ZnO nanorods fabricated by a microemulsion method

We have studied photoluminescence (PL) properties of Eu-doped ZnO (ZnO:Eu) nanorods fabricated by a microemulsion method. The ZnO:Eu nanorods have a hexagonal crystal structure and exhibit a sharp luminescence due to the intra-4f transitions of Eu3+ ions. The excitation energy and temperature dependence of the PL intensity show that the Eu3+-related PL efficiency is determined by the energy relaxation process of excited Eu3+ ions, rather than by the energy transfer process from ZnO nanorods to Eu3+ ions. The energy transfer and luminescence processes in ZnO:Eu nanorods are discussed.