关键词: 稀土离子, 磷酸镧, 纳米棒束, 掺杂, 发光

Rare earth ions (Ce³⁺, Tb³⁺) doped LaPO₄ nano-structural materials were synthesized by hydrothermal treatment at 180 ℃ for 24 h, and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence (PL) spectra and kinetic decay curves. The morphology, phase and luminescent properties of the obtained samples can be controlled through altering the variety of additives and doped rare earth ions, and the doping concentration of rare earth ions. The results indicate that when the doping concentration is as low as 5 mol%, Ce³⁺ or Tb³⁺ ion-doped LaPO₄ materials are composed of single-crystalline nanorods with the length of 200～550 nm and the diameter of 12～30 nm, and have monoclinic phase structure. These nanorods with small size trend to assemble through shoulder-by-shoulder to form the nanorod bundles. When the concentration of Ce³⁺ ions increases from 5 to 30 mol%, the phase structure of LaPO₄ nanorods transforms from monoclinic to hexagonal phase, whereas the doping concentration of Tb³⁺ ions at the same range can not result in the phase transformation. The length of the obtained nanorod bundles is at the range from 150 nm to 2.0 μm and the value can be controlled by altering the variety and the doping concentration of the doped rare earth ions, while the diameter of the nanorod bundles is mainly kept at 40～60 nm. The addition of different additives can improve the uniform feature of the obtained nanorod bundles and lead to the alteration of the length of these nanorod bundles. Under the excitation of ultraviolet light, Ce³⁺ or Tb³⁺ ion-doped LaPO₄ nanorod bundles exhibit the characteristic emission of the corresponding doping ions, and the Ce³⁺ and Tb³⁺ ions co-doped samples exhibit strong green emission of Tb³⁺ ions due to the efficient energy transfer between Ce³⁺ and Tb³⁺ ions.

Key words: rare earth ion, LaPO₄, nanorod bundle, doping, luminescence