Self-assembled 3D flower-like NaY(MoO4)2:Eu microarchitectures: Hydrothermal synthesis, formation mechanism and luminescence properties

Self-assembled 3D flower-like NaY(MoO₄)₂:Eu³⁺ microarchitectures were successfully synthesized by a glycine-assisted hydrothermal method at 180 °C. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM) were employed to characterize the as-obtained products. It was found that morphology modulation could be easily realized by changing the time of hydrothermal reaction system. 3D flower-like NaY(MoO₄)₂:Eu³⁺ microarchitectures were formed with 72 h reaction time. The formation mechanism for flower-like architecture was proposed on the basis of a series of time-dependent experiments. The NaY(MoO₄)₂:Eu³⁺ powders obtained can be effectively excited by 396 nm light, and exhibit strong red emission around 615 nm, attributed to the Eu³⁺⁵D₀ → ⁷F₂ transition. An investigation on the photoluminescence (PL) properties of NaY(MoO₄)₂:Eu³⁺ obtained revealed that the luminescence properties were correlated with the morphology and size.