Uniform AMoO4:Ln (A=Sr2+, Ba2+; Ln=Eu3+, Tb3+) submicron particles: Solvothermal synthesis and luminescent properties

Rare-earth ions (Eu3+, Tb3+) doped AMoO4 (A=Sr, Ba) particles with uniform morphologies were successfully prepared through a facile solvothermal process using ethylene glycol (EG) as protecting agent. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS), Fourier transform infrared spectroscopy (FT-IR), photoluminescence (PL) spectra and the kinetic decays were performed to characterize these samples. The XRD results reveal that all the doped samples are of high purity and crystallinity and assigned to the tetragonal scheelite-type structure of the AMoO4 phase. It has been shown that the as-synthesized SrMoO4:Ln and BaMoO4:Ln samples show respective uniform peanut-like and oval morphologies with narrow size distribution. The possible growth process of the AMoO4:Ln has been investigated in detail. The EG/H2O volume ratio, reaction temperature and time have obvious effect on the morphologies and sizes of the as-synthesized products. Upon excitation by ultraviolet radiation, the AMoO4:Eu3+ phosphors show the characteristic 5D0–7F1–4 emission lines of Eu3+, while the AMoO4:Tb3+ phosphors exhibit the characteristic 5D4–7F3–6 emission lines of Tb3+. These phosphors exhibit potential applications in the fields of fluorescent lamps and light emitting diodes (LEDs).