Hydrothermal synthesis and luminescent properties of LuBO3:Tb3+ microflowers

Hexagonal vaterite-type LuBO3:Tb3+ microflower-like phosphors have been successfully prepared by an efficient surfactant- and template-free hydrothermal process directly without further sintering treatment. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectrometry, transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), photoluminescence (PL) and cathodoluminescence (CL) spectra as well as kinetic decays were used to characterize the samples. The as-obtained phosphor samples present flowerlike agglomerates composed of nanoflakes with thickness of 40 nm and high crystallinity in spite of the moderate reaction temperature of 200 deg. C. The reaction mechanism has been considered as a dissolution/precipitation mechanism; the self-assembly evolution process has been proposed on homocentric layer-by-layer growth style. Under ultraviolet excitation into the 4f8→4f75d transition of Tb3+ at 248 nm (or 288 nm) and low-voltage electron beam excitation, LuBO3:Tb3+ samples show the characteristic green emission of Tb3+ corresponding to 5D4→7F6,5,4,3 transitions with the 5D4→7F5 transition (542 nm) being the most prominent group, which have potential applications in fluorescent lamps and field emission displays. - Graphical abstract: Hexagonal vaterite-type LuBO3:Tb3+ microflower-like phosphors have been successfully prepared by a simple and mild hydrothermal process directly. The reaction mechanism has been considered as the dissolution/precipitation mechanism; the self-assembly evolution process has been proposed on homocentric layer-by-layer growth style. The luminescent properties of the as-obtained LuBO3:Tb3+ samples have been investigated in detail, which shows it is a good green-emitting phosphor in fluorescent lamps and field emission displays potentially