Enhanced up-conversion emission in Er3+-doped barium-natrium-yttrium-fluoride phosphors by alkali ion introduction under 1550 nm excitation

In this work, multi-component fluoride phosphors BaxNay-nMnYzF2x+y+3z+3m : Er-m(3+) (M = Li and K) sensitive to 1550 nm were synthesized by the low-temperature combustion synthesis (LCS) method. The optimum batch formula was determined by orthogonal experiments. The effects of introducing alkali ions (Li+, K+) on phase formation and luminescence intensity were systematically studied. The results indicate that the luminescence intensity of 0.2 mol% Li+-introduced nanoparticles is obviously enhanced, and the diffraction peak is shifted to the direction of a smaller diffraction angle, which is attributed to the lattice expansion caused by Li+ ions entering the lattice gap that changes the local symmetry of Er3+ ions. The phase composition and morphology of phosphors were analyzed by X-ray diffraction and scanning electron microscopy (SEM). The product exhibited Er3+ ion characteristic emission under 1550 nm excitation, and its luminescence mechanism was studied. This work provides a new idea for improving the luminescence intensity of up-conversion luminescent materials (UCL) under 1.5 mu m excitation.

Automated summary

In this study, multi-component fluoride phosphors sensitive to 1550 nm were synthesized using the LCS method, with Li+ and K+ ions introduced to enhance luminescence intensity. The introduction of 0.2 mol% Li+ significantly enhanced luminescence intensity and caused lattice expansion.