3D-hierarchical Lu2O2S:Eu3+ micro/nano-structures: controlled synthesis and luminescence properties

Abstract

Several three-dimensional (3D) hierarchical architectures of Lu₂O₂S:Eu³⁺ have been successfully synthesized via a simple solvothermal method with polyvinylpyrrolidone (PVP) as surfactant, followed by a subsequent calcination process. The as-prepared products were well characterized by means of X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), and photoluminescence (PL) spectra. The results reveal that the morphologies of precursors can be tuned by altering pH value of the reaction system. Detailed investigation indicates that the formations of different micro-structures are dominated by different growth mechanisms. The as-formed precursors could transform into Lu₂O₂S:Eu³⁺ with their original hierarchical structures maintained. Under ultraviolet (UV) excitation, the Lu₂O₂S:Eu³⁺ micro-architectures exhibit strong red emission corresponding to the ⁵D₀→⁷F₂ transition of the Eu³⁺ ions. Furthermore, the dependence of Lu₂O₂S:Eu³⁺ luminescence performance on different morphologies has been involved in the present work.