3D Hierarchical Architectures of Sodium Lanthanide Sulfates: Hydrothermal Synthesis, Formation Mechanisms, and Luminescence Properties

Sodium lanthanide sulfate NaLn(SO4)(2)center dot H2O (Ln = Y, La to Yb) nano/microcrystals with multiform morphologies were successfully synthesized by a facile and effective hydrothermal method. The photoluminescence properties of the Ce3+ and Tb3+ single-doped as well as the Ce3+-Tb3+ codoped NaY-(SO4)(2)center dot H2O microsheaves were characterized. The results reveal that the existence of the Ce3+ ions can dramatically enhance the emission intensity of the Tb3+ ions, due to an efficient energy transfer from the Ce3+ to the Tb3+ ions. The critical energy-transfer distance between the Ce3+ and the Tb3+ ions was calculated by methods of concentration quenching and spectral overlapping. Analysis and calculation reveal that the dipole-quadrupole interaction should be mainly responsible for the energy transfer.