Hydrothermal synthesis of ordered nanolamella-composed Y2O3:Eu3+ architectures and their luminescent properties

A series of Y2O3:Eu3+ samples with interesting three-dimensional (3D) microarchitectures were synthesized through a facile hydrothermal method in the presence of hexamethylenetetramine (HMT) followed by a subsequent heat treatment. The as-formed precursor via the hydrothermal process could transform to cubic Y2O3 with the same morphology after annealing at 500 °C for 2 h. The Y2O3 microstructures, with an average diameter about 10-20 μm, were composed of nanolamellas with thickness of about 50 nm. Besides a probable self-assembly mechanism, the Ostwald Ripening process was proposed to explain the formation of the architectures on the basis of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations. The as-synthesized lamella-composed Y2O3:Eu3+ samples showed a strong red emission corresponding to 5D0→7F2 transition (612 nm), suggesting promising applications in optoelectronics.