Low temperature nanocasting synthesis of lanthanide ions (Ln = Tb, Eu, Dy) doped CaWO4 mesoporous structure with efficiently luminescent properties

In this work, we report on the construction of lanthanide doped CaWO4 mesoporous structure with efficiently luminescent properties. Using citric acid as the capping agent and SBA-15 as the nanocasting template, lanthanide doped CaWO4 samples with mesostructure were successfully prepared at low temperature for the first time. The samples were carefully characterized by X-ray diffraction, transmission electron microscopy, N-2 adsorption-desorption, Fourier transform infrared spectroscopy, and luminescence spectra. It is found that the lanthanide doped CaWO4 showed mesostructure with high specific surface area, large pore volume, and mesoporous pore size distribution. Photoluminescence measurements indicated that lanthanide doped CaWO4 mesostructure exhibited highly efficient luminescent properties in comparison with conventional randomly deposited lanthanide doped CaWO4 nanoparticles due to superior interparticle connectivity of mesostructures that can suppress the energy losses and reduce surface quenching centers. By altering lanthanide ions, mesoporous CaWO4 showed multi-color emission such as green, red, and dark cyan under single-wavelength excitation. (C) 2012 Elsevier Inc. All rights reserved.