Effect of Cr2O3 on the structural, optical and dielectric studies of LiF-SrO-B2O3 glasses

The melt quench technique was involved in synthesizing the glass system LiF-SrO-B2O3 alloyed with Cr2O3 in the range of 0 to 0.25 mol%. The aperoidic nature of these glasses was affirmed by the X-ray diffraction (XRD). These glasses were analyzed by contemplating the dielectric characteristics (a.c. conductivity, σac, dielectric constant, ε’, and dielectric loss, tanδ etc.,), spectroscopic properties such as electron spin resonance (ESR) optical absorption and Fourier transform infrared (FTIR) analysis. The optical absorption spectra evinced two bands which are features of Cr3+ ions in the octahedral domain. Using absorption edges, Urbach energies and optical band gap of these samples were estimated. The hike in the Cr3+ ions in the glass C5 (0.05 mol% of Cr2O3) is confirmed by the proliferation in the ESR signal intensity and optical absorption peak. The maximum a.c. conductivity of glass C5 was due to the dominant presence of Cr3+ ions. FTIR bands revealed that at 0.05 mol% of Cr2O3, BO4 units were converted into BO3 units. It is perceived that the semiconducting nature of glass C5 was the highest among all the prepared glasses.