Effect of Ho3+ ion concentration on structure and spectroscopic properties of LiPbB5O9:Ho3+ phosphor

Lithium lead borate (LiPbB5O9:Ho3+) phosphors doped with distinct concentrations of Ho3+ ions were prepared by solid state reaction technique. Structural characteristics were studied from X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and FT-Raman characterizations. Spectroscopic properties were studied from UV-Vis-NIR and photoluminescence (PL) spectra. From XRD investigations, crystallite sizes were calculated from Debye-Scherrer (D-S) and William-Hall (W-H) methods. Optical energy band gaps were calculated by using Tauc's relation for direct and indirect allowed transitions. The emission spectra of LiPbB5O9:Ho3+ phosphors were recorded by monitoring the excitation wavelength at lambda(exc) = 397nm. Lifetime decay curves of S-5(2) energy level of Ho3+ ion were studied for distinct concentrations of Ho3+ ions. Energy transfer mechanism was investigated for LiPbB5O9:Ho3+ phosphor. Concentration quenching was observed at 0.08 mol% of Ho3+ concentration among various concentrations. CIE color coordinates were computed and they showed the greenish-yellow region for various Ho3+ concentrations. The present, LiPbB5O9:0.08Ho(3+) phosphor may be useful for the greenish-yellow emitting phosphor applications. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

Lithium lead borate phosphors doped with Ho3+ ions were prepared by solid state reaction technique. The structural characteristics were studied using XRD, FTIR, and FT-Raman, while the spectroscopic properties were studied using UV-Vis-NIR and PL spectra. The emission spectra, lifetime decay curves, energy transfer mechanism, concentration quenching, and CIE color coordinates of the phosphors were also investigated.