Synthesis and upconversion properties of Ln3+ doped YOF nanofibers

YOF nano/micro-crystals: morphology controlled hydrothermal synthesis and luminescence properties

“…33,47 A great mass loss occurs between 250 to 350 °C which is probably attributed to the decomposition of the precursors, and the third one should be caused by the further decomposition of the precursors and the formation of YOF at 360-550 °C, basically agreeing well with the above results. 38 It should be mentioned that doping with a small amount of other Ln 3+ in the YOF host does not change the phase, crystallization, and morphology of the YOF products in our present work. So here we only take the YOF without doped ions as a typical example to explain the morphologies of the products.…”

“…[30][31][32][33] Until now, YOF nano/micro-crystals with various morphologies have been successfully synthesized by several techniques such as the solid state reaction, the sol-gel method, a molten salt synthesis, the thermolysis method and the electrospinning process. [34][35][36][37][38][39] However, these approaches suffer from drawbacks such as large crystallites, harsh reaction conditions, high environment loads and complicated processes, which severely hamper their potential application.…”

Synthesis, morphology and spectroscopic properties of red-luminescent rhombohedral YOF: Yb3+, Er3+ powders

“…And it has been known that phase transition among the above phases may be obtained by controlling the reaction temperature. 19 The sol-gel method, on the other hand, is a wet chemical technique with low cost and high yield employed in producing single-or multi-phase oxy-uoride powders. For example, Dutton et al reported a solid-state synthetic route employing polytetrauoroethylene and the rare-earth oxides, for the purpose of YOF preparation, which need a post formation annealing and a second ring process with a temperature higher than 800 C. 12 Rakov and Maciel prepared Er 3+ and Tm 3+ co-doped YOF powders with spectrally pure red color emission by combustion synthesis combined with a heat treatment procedure at 750 C for 2 h. The results showed that the energy transfer (ET) process between Er 3+ and Tm 3+ ions in YOF was much more efficient than that observed in Y 2 O 3 powder.…”

Morphology control and multicolor-tunable luminescence of YOF:Ln3+ (Ln = Eu, Tb, Dy, Tm) nano-/microcrystals

“…[12][13][14][15] However, the majority of research on LnOF have been done on their bulk crystals or thin films obtained by some limited chemical routes, such as high-temperature-based solid-state reaction, hydrothermal precipitation, the sol-gel method, and chemical vapor deposition (CVD), while quite a few reports touch upon the fabrications of monodisperse LnOF based luminescent materials with high quality. 14,[16][17][18] Recently, Lin et al prepared monodisperse YOF nano-/microcrystals through a convenient modified urea-based homogeneous precipitation (UBHP) technique, but just got several morphologies and they studied only single doped luminescence properties under ultraviolet excitation. 19 Hence, in this study varieties of well-defined morphologies, including submicro spheres, ellipsoids, nanorods, microspindles and spindle nanorod bundles, have been synthesized using a convenient modified urea-based homogeneous precipitation technique.…”