Effect of samarium oxide addition on the structural, thermal, and optical properties and photoluminescence of lithium borate glass

Abstract

The samples were prepared in compliance with the form 33 Li2O–66 B2O3—(1-x) AgF—x Sm2O3, where x = 0, 0.25, 0.5, and 0.75. Powdered samples were converted to a glassy state via melting and quenching. The glassiness of the prepared samples was examined using X-ray diffraction (XRD) and Differential Thermal Analysis (DTA). From the absorption spectra of the prepared glass samples, the band gap in the optical spectrum changed slightly in the range of 3.45, whereas the Urbach energy decreased from 0.32 to 0.267 eV. The fluctuations of the optical band gap and Urbach energy can be attributed to variations in the glass structure. Sm3 + emitted intense reddish-orange light under blue and UV light excitation. There are six excitation bands in the Sm3+ excitation spectrum situated in the blue and UV regions, peaking at 361.7, 374, 400, 417, 462, and 475 nm, which are attributed to the transitions from 6H5/2 to 4D3/2, 6P7/2, 6P3/2, 6P5/2, 4I13/2, and 4I11/2 respectively. The transition from 6H5/2 to 6P3/2 had the highest intensity and was associated with a peak at 400 nm. The bright yellow, reddish-orange, and red emission bands of the Sm3+ ions in the oxide glasses are related to the 4G5/2 → 6H5/2, 4G5/2 → 6H7/2, and 4G5/2 → 6H9/2 emission transitions, respectively.