Synthesis and characterization of lithium niobium borate glasses containing neodymium

Abstract

A series of (90–x)Li2B4O7-10Nb2O5-xNd2O3 glass samples (x=0, 5 mol.%, 10 mol.%, 15 mol.%, 20 mol.% and 25 mol.%) were synthesized using melt quenching technique. X-ray diffraction (XRD), differential thermal analyzer (DTA), Fourier transformed infrared (FTIR), ultraviolet-visible-near-infrared (UV-Vis-NIR) spectrometer and photoluminescence (PL) spectroscopic characterizations were made to examine the influence of Nd3+ concentration on the physical, structural and optical properties. Various physical properties such as glasses density, molar volume, thermal stability, ion concentration, polar on radius, inter-nuclear distance, field strength, cut-off wavelength, energy band gap and Urbach energy were calculated. The samples were amorphous in nature and confirmed from XRD pattern. The FTIR spectra revealed the presence of BO3 and BO4 functional groups. UV-Vis-NIR spectra exhibited nine prominent bands centered at 353, 430, 475, 524, 583, 681, 745, 803, 875 nm corresponding to the transitions from the ground state to 4D3/2, 2P1/2, 2G9/2, 4G7/2, 4G5/2, 4F9/2, 4F7/2, 4F5/2, 4F3/2 excited states, respectively. Moreover, the emission spectra at 355 nm excitation displayed three peaks centered at 903 nm (4F3/2?4I9/2), 1059 nm (4F3/2?4I11/2) and 1333 nm (4F3/2?4I13/2), respectively. Fluorescence lifetime was recorded between 53.69 to 28.43 µs. It was found that varying concentration of Nd3+ ions strongly affected the physical, structural and optical properties of the glass samples.