A lanthanide ion-doped Ba3Sc2F12 phosphor: hydrothermal synthesis, morphological control, energy transfer, and temperature-sensing performance

Abstract

Ba₃Sc₂F₁₂ crystals were synthesized by a facile one-step hydrothermal method with Ba/Sc raw material in a ratio of 3 : 2. With the F/Sc ratio increasing from 4 to 8, the obtained crystal's morphology evolved gradually from a strip to a chocolate shape; further, the use of the additives, such as CTAB and EDTA, the obtained crystal's morphology changed from strip to cubic. The energy transfer of Ce³⁺ → Tb³⁺ in the Ba₃Sc₂F₁₂ host was also explored, and it was found to belong to a dipole–dipole interaction mechanism; the color of the light could be adjusted from blue-violet to green due to the different energy transfer efficiencies at different Ce³⁺ and Tb³⁺ ion-doping concentrations. Because of the thermal coupling level of Er³⁺ (²H_11/2 → ⁴I_15/2 and ⁴S_3/2 → ⁴I_15/2), Ba₃Sc₂F₁₂:14%Yb³⁺,2%Er³⁺ phosphors showed an excellent temperature-sensing ability with S_A(max) = 0.0043 K⁻¹ and T_max = 523 K, which are much better than the previously reported values for Yb³⁺/Er³⁺ co-doped systems. The as-prepared lanthanide ion-doped phosphors might have potential to serve as color light/displays and temperature control/sensors.