Air-Annealing Impact on Spectroscopic Properties of the Nd3+ (1 mol %):YF3 Phosphor

We report on the synthesis of Nd3+ (1 mol %):YF3 phosphors obtained via co-precipitation from aqueous solutions. Annealing in air of the synthesized Nd3+ (1 mol %):YF samples resulted in the additional formation of an oxygen-vacancy complex (OF–OV complex). The luminescence intensity of the OF–OV complex increased by a factor of 12.5 relative to the non-annealed sample. The impact of oxygen-vacancy defects (OF–OV complex) on the luminescent properties of samples that doped with Nd3+ ions in temperature range from 80 to 320 K was studied. It was suggested that the thermal trapping of charge carriers by the defective OF–OV complex at low temperatures (≈80 K) leads to an increase in the intensity of defect luminescence compared with the luminescence of Nd3+ ions and vice versa. It was found that the energy transfer between the OF–OV complex and Nd3+ ions is unlikely.