Efficient and thermally stable red luminescence from nano-sized phosphor of Gd₆MoO₁₂:Eu³⁺

A novel red-emitting nano-phosphor of Eu³⁺-doped Gd₆MoO₁₂ was successfully synthesized by the Pechini method. The crystalline phase was confirmed by X-ray powder diffraction analysis. The morphology of the nano-phosphor was analyzed by scanning electron microscopy, indicating a good crystallization with particles smaller than 500 nm. The luminescence properties such as photoluminescence spectra and decay curves were investigated. The phosphors can be efficiently excited by near-ultraviolet (near-UV) light and exhibit a bright red luminescence around 613 nm ascribed to the forced electric dipole transition ⁵D₀→⁷F₂ of Eu³⁺ ions. The thermal stabilities were investigated from the temperature-dependent luminescence decay curves (lifetimes) and spectra intensities. The luminescence properties in relation to applications in white light-emitting diodes (W-LEDs) such as the absolute luminescence quantum efficiency, excitation wavelength, and color coordinates were discussed. The Gd₆MoO₁₂:Eu³⁺ nano-phosphor is a promising red-emitting candidate for the fabrication of W-LEDs with near-UV chips.