A simple method to prepare Ln(OH) 3 (Ln = La, Sm, Tb, Eu, and Gd) nanorods using CTAB micelle solution and their room temperature photoluminescence properties

Abstract

The stable and crystalline pure phase Ln(OH) 3 (Ln = La, Sm, Tb, Eu, and Gd) nanorods with diameters of approximately 15–90 nm and lengths of 120–500 nm were synthesized using cationic surfactant (cetyltrimethylammonium bromide, CTAB) micelle solution at room temperature. X-ray diffraction (XRD) spectra, Fourier transformed infrared (FTIR) spectrum, transmission electron microscopy (TEM), high-resolution TEM (HRTEM) and Raman spectroscopy were used to examine the morphologies and microstructures to find out the cause. The four observed Raman peaks indicated the typical hexagonal phase, which was in agreement with the X-ray diffraction results. A possible formation mechanism of these Ln(OH) 3 nanorods was proposed. The results suggest that this process may be a convenient and effective approach to prepare rare-earth hydroxides with 1D nanostructures. Room temperature photoluminescence (RTPL) properties were investigated under the excitation of 275 nm. The samples exhibited the emission peaks of room temperature photoluminescence.