Controlled synthesis and characterization of large-scale, uniform Dy(OH)3 and DY2O3 single-crystal nanorods by a hydrothermal method

Large-scale and uniform Dy(OH)(3) nanorods have been successfully prepared by a simple hydrothermal method. Subsequent thermal decomposition of the as-prepared Dy(OH)3 nanorods produced Dy2O3 nanorods. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), thermogravimetric analysis (TGA) and differential thermal analysis (DTA) have been employed to characterize the products. XRD and SAED patterns showed the Dy(OH)(3) nanorods were a pure hexagonal phase and single-crystal in nature. FMSEM and TEM images showed that the diameters of the Dy(OH)(3) nanorods ranged from 40 to 50 nm and the lengths ranged from 300 to 500 nm. The Dy2O3 nanorods inherited their parents' morphology, but their size is slightly shrunk in comparison with the Dy(OH)(3) nanorods. The formation mechanism of Dy(OH)(3) nanorods is discussed. Photoluminescence measurement shows that the nanorods have two emission peaks around 490 and 575 nm, which should come from the electron transition from F-4(9/2) to H-6(15/2) levels and F-4(9/2) to H-6(13/2) levels, respectively.