Synthesis and Luminescence Properties of Sheaflike TbPO₄ Hierarchical Architectures with Different phase Structures

Sheaflike terbium phosphate hydrate hierarchical architectures composed of filamentary nanorods have been fabricated by a hydrothermal method. The X-ray diffraction patterns and thermogravimetric/differential thermal analysis investigations reveal that the obtained terbium phosphate hydrate has a structural formula of TbPO 4 ·H 2 O, which can be readily indexed to the hexagonal phase GdPO 4 · n H 2 O in JCPDS file 39-0232. The evolution of the morphology of the products has been investigated in detail. It is found that the addition of CTAB and Na 2 H 2 L (disodium ethylenediamine tetraacetate) plays an important role in controlling the final morphology of the products. A possible formation mechanism of the sheaflike architectures was proposed according to the experimental results and analysis. In addition, the phase structure of the product changes to monoclinic phase when it is annealed at 750 °C for 2 h in N 2 −H 2 atmosphere. Tetragonal phase TbPO 4 can be obtained when annealed temperature increases to 1150 °C. It was observed that some changes take place on the morphology and optical properties of the products annealed at different temperatures.