Eu3+ doped lutetium molybdenum oxides: Synthesis, optical properties, thermal behavior, and LED packaging

Some lutetium molybdenum oxides were synthesized through a solid-state reaction method. By adjusting the molar ratios of raw materials of Lu2O3 (Eu2O3) to MoO3, Eu3+ doped lutetium molybdenum oxides Lu2MoO6, Lu2Mo2O9, Lu-2(MoO4)(3), and Lu6MoO12 were obtained. The materials were characterized by X-ray diffraction (XRD) patterns, scanning electron microscope (SEM) images, energy-dispersive spectra (EDS), diffuse reflection (DR) spectra, photoluminescence (PL) excitation and emission spectra, luminescence decay curves, and temperature dependent integrated emission spectra. Enhanced excitation and emission spectra were recorded at high temperatures. Possible energy transfer processes were proposed to explain the excitation and emission spectra. By combining some phosphors with near ultraviolet (NUV) chips, the obtained light emitting diodes (LEDs) gave red light under forward bias current. The results suggest that the obtained Eu3+ doped lutetium molybdenum oxides have potential applications in phosphor converted based NUV LEDs.