Microwave-assisted controllable synthesis of 2D and 1D Eu³⁺-Y₂O₃ micro/nanoparticles and their photoluminescence properties

Rare earth elements doped yttria is a group of important functional materials used in various applications. In this work, Eu³⁺-Y₂O₃ particles with different morphology including nanoplates, porous nanoplates, quasi-triangular microprisms, hexagonal microprisms, microcylinders and nanorods have been synthesized by a facile two-step method without using any template or surfactant. The mixture of Eu(NO₃)₃, Y(NO₃)₃ and NaOH solution were irritated by microwave for 10 ​min to form the intermediate hybrid precursors, and the final Eu³⁺-Y₂O₃ were obtained by calcining the intermediate powder at 600 ​°C for 3 ​h. The morphologies, microstructure, crystal phase and composition of the samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and thermal analysis (TG–DSC) in detail. The results show that the shapes can be controlled effectively from two dimension (2D) to one dimension (1D), and the size can be adjusted from microscale to nanoscale by changing the ratio of OH⁻/Re³⁺ only. The photoluminescence (PL) intensity and decay time of the particles vary significantly with the morphologies.