Synthesis and luminescence properties of CaGd2(MoO4)(4):Ln(3+) (Ln = Eu3+, Tb3+, Dy3+ and Sm3+) phosphors

Abstract

The uniform monodisperse rectangular-like rare-earth-activated CaGd2(MoO4)4:Ln3+ (Ln?=?Eu3+, Tb3+, Dy3+ and Sm3+) phosphors have been synthesized by conventional solid state reaction method. The prepared phosphors were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM) and photoluminescence (PL) spectroscopy measurements. The XRD and FTIR results showed a scheelite-type tetragonal structure for the prepared powder samples. FTIR spectra exhibited a high absorption band situated at around 846?cm-1, which was ascribed to the Mo–O antisymmetric stretching vibrations into the [MoO4]2- tetrahedron groups and the SEM image reveals particle size in the range of 120–160?nm. The excitation/emission spectra and life times were measured to characterize the luminescent properties of the phosphors. All properties show that CaGd2(MoO4)4:Ln3+ (Ln?=?Eu3+, Tb3+,Dy3+ and Sm3+) compounds are a very appropriate red, green, yellow and orange-red emitting light–emitting phosphors promising for lighting applications.