Luminescence properties and thermal stabilities of Yb3+, Tm3+ co-doped SrGd2(WO4)2(MoO4)2 nano-crystals

Novel up-conversion luminescent SrGd2(WO4)2(MoO4)2:Yb3+/Tm3+ nano-crystals were synthesized via the hydrothermal method. The average particle size of the as-prepared sample was ∼55 nm. The thermal stability and luminescence properties of samples synthesized at different calcination temperatures were investigated in this work. Results show that the sample exhibits optimal overall performance, including excellent thermal stability, with CYb3+ doping at 6 mol. %, CTm3+ doping at 1.5 mol. %, and a corresponding calcination temperature of 723 K. The samples were characterized using x-ray diffraction, scanning electron microscopy, transmission electron microscopy, up-conversion luminescence spectra, and luminescence decay curves. These characterizations confirm that the as-prepared sample has high crystallinity, belongs to the tetragonal crystal system, and shows good thermal stability. Besides, the sample exhibits stable, uniform luminescence color with high color purity, a distinct advantage. All these merits give the sample high practical application potential in the field of optical devices.