Energy transfer and color tunable up-conversion luminescence in PrF3 and YbF3 co-doped SrF2 transparent ceramics

Near-infrared pumped up-conversion luminescent PrF 3 and YbF 3 co-doped SrF 2 ceramics were fabricated by the hot-pressing sintering technique, and the pellets were transparent with a primrose yellow appearance. The influence of YbF 3 co-doping levels on the optical qualities and microstructures of ceramics was investigated. We identified the mechanisms to realize up-conversion luminescence in the visible range from 3 P 0,1 levels (Pr 3+ ) under near-infrared wavelength pumping sources other than the near ultraviolet to blue region photons. Yb 3+ ions inducing a broad and intense absorption band at the 900–1050 nm region, and the absorption coefficient and cross-section at 980 nm are 7.57 cm −1 and 4.19 × 10 −21  cm 2 in the ceramic co-doped with 15 wt% YbF 3 , respectively. The intense up-conversion luminescence bands at 480, 520, 540, and 600 nm under 980 nm excitation were attributed to 3 P 0 → 3 H 4 , 3 P 1 → 3 H 5 , 3 P 0 → 3 H 5 and 1 D 2 → 3 H 4 transitions of Pr 3+ ions, respectively.