Synthesis and upconversion emission of rare earth-doped olive-like YF3 micro-particles

The olive-like YF3 micro-particles were fabricated via a two-step route. The precursor NH4Y3F10 nano-cages sized 8 nm with hollow interiors were first synthesized in a solid reaction at room temperature. In the course of subsequent hydrothermal treating, the unstable NH4Y3F10 nano-cages were decomposed, resulted in the formation of Y(OH)1.63F1.37 micro-tubes. Prolonging the hydrothermal reaction induced the further decomposition of Y(OH)1.63F1.37 to produce YF3 nano-crystals, which then aggregated together forming the final olive-like YF3 micro-particles. For the Er3+/Yb3+ co-doped olive-like YF3 micro-particles, intense visible upconversion emissions were measured under 976 nm excitation owing to the partition of rare earth ions in the lattice, indicating this material a promising luminescent host.