Dielectric and spectroscopic features of Li2O/Fe2O3/In2O3/P2O5 glass systems doped with Bi2O3

Abstract A comprehensive exploration of penta glass systems’ spectroscopic and dielectric characteristics was achieved, specifically for the glass series 20Li₂O–15Fe₂O₃–5In₂O₃–xBi₂O₃–(60–x) P₂O₅(x = 0, 2.5, 5, 7.5, 10, and 12.5 mol %). Both average phosphorus-phosphorus separation and crystalline volume were found to decrease depending on Bi₂O₃ content. The optical band gap obtained from diffuse reflectance spectra (DRS) is found to be in the range of 1.58–1.81 eV with increasing bismuth oxide content. The optical band gap increases with bismuth content, which can be ascribed to structural changes and the reduction in non-bridging oxygen (NBO). A decrease in optical parameters, viz., refractive index (2.945–2.824), molar refractivity (32.45–29.12), and molar polarizability values (12.88–11.56), occurs with Bi₂O₃ content. The glasses have been designated as semiconductors due to an increase in the metallization criteria values (M lie between 0.2811 and 0.3008). The obtained results exhibit contraction in the bonds of the glass matrix and an increase in rigidity of the structure at a higher content of Bi₂O₃.The dc and ac conductivity of the studied glasses were affected by the O/P ratio, as they attained high values at O/P > 3.0. The asymmetrical shape of the Nyquist semicircle indicated that the glasses behavior deviated from Debye relaxation. The overall behavior of the electrical properties of the studied glasses revealed their semiconducting performance. The examined glasses could be good choices for photonic applications.