Hydrothermal synthesis, characterization and up/down-conversion luminescence of barium rare earth fluoride nanocrystals

•Mixed hydrothermal system H2O–OA (EDA)–O-A(LO-A) is used for synthesis.•Barium rare earth fluoride nanocrystals are synthesized comprehensively.•Luminescence for down-conversion and up-conversion are obtained for these systems.

Mixed hydrothermal system H2O–OA (EDA)–O-A(LO-A) is developed to synthesize barium rare earth fluorides nanocrystals (OA = oleylamine, EDA = ethylenediamine, O-A = oleic acid and LO-A = linoleic acid). They are presented as BaREF5 (RE = Ce, Pr, Nd, Eu, Gd, Tb, Dy, Y, Tm, Lu) and Ba2REF7 (RE = La, Sm, Ho, Er, Yb). The influence of reaction parameters (rare earth species, hydrothermal system and temperature) is checked on the phase and shape evolution of the fluoride nanocrystals. It is found that reaction time and temperature of these nanocrystals using EDA (180 °C, 6 h) is lower than those of them using OA (220 °C, 10 h). The photoluminescence properties of these fluorides activated by some rare earth ions (Nd3+, Eu3+, Tb3+) are studied, and especially up-conversion luminescence of the four fluoride nanocrystal systems (Ba2LaF7:Yb, Tm(Er), Ba2REF7:Yb, Tm(Er) (RE = Gd, Y, Lu)) is observed.

Graphical abstractLanthanide ions doped bare earth rare earth fluoride nanocrystals are synthesized by hydrothermal technology and characterized. The down/up-conversion luminescence of them are discussed.Figure optionsDownload full-size imageDownload as PowerPoint slide