Highly uniform Gd(OH)3 and Gd2O3:Eu3+ hexagram-like microcrystals: glucose-assisted hydrothermal synthesis, growth mechanism and luminescence property

Abstract Monodispersed and uniform Gd(OH) 3 microcrystals with novel hexagram-like morphology have been successfully prepared through a simple and green hydrothermal process with the assistance of glucose. The results of control experiments revealed that the glucose concentration in the reaction system was an important factor, which affected the morphology of the Gd(OH) 3 microcrystals significantly. On the basis of time-dependent experiments, the growth mechanism of the Gd(OH) 3 hexagrams was discussed. Furthermore, the Gd 2 O 3 and Eu 3+ -doped Gd 2 O 3 hexagram-like microcrystals, inheriting the Gd(OH) 3 precursors' morphology, were obtained during a direct annealing process in air. The corresponding Gd 2 O 3 :Eu 3+ hexagram-like microcrystals exhibit strong red emission pertaining to the 5 D 0 → 7 F 2 transition of the Eu 3+ ions under UV light, which have potential applications in novel optoelectronic devices.