Impact of copper ions on physical, structural, spectroscopic, and dielectric properties of Bi2O3–CaO–P2O5–B2O3 glasses

Abstract

The objective of the present study is to investigate the physical, structural, spectroscopic and dielectric studies on the multi component 3Bi2O3–10CaO–20P2O5-(67-x)B2O3: xCuO (0 ≤ x ≤ 0.9 mol%) glass network. The specimens were fabricated by the melt quenching and heat treatment method. X-ray diffraction (XRD) approves the amorphous temperament of glasses. To prove the existence of copper ions and their valence states, the optical absorption and electron spin resonance (ESR) spectra of the glasses were investigated. Optical absorption spectra exhibited a dominant band virtually at 850 nm as a result of copper ions. Optical band gap energy (Eo) and Urbach energy (ΔE) of specimens were estimated. It is observed that Eo exhibited a decreasing tendency with an increase in the concentration of CuO but the values of ΔE showed a reverse trend. These outcomes promoted the intensification of dopant ions in the specimens. Investigations on electron spin resonance (ESR) spectra authenticated occupancy of copper ions in work-pieces. Amplification in intensity of signal indicates magnification of Cu2+ ions. The spin-Hamilton parameters (SHP) of samples were determined. Fourier transform infrared (FTIR) studies reveal the structural variations in the glasses. The presence of conventional bismuth, phosphate and borate bands was displayed by the FTIR curves of the specimens. The dielectric studies indicate the change in electrical properties of the glasses. The dielectric properties of the glasses were analyzed in a substantial range of frequencies (1–103 kHz) and temperatures (30–300 °C). All outcomes are in favor of decrease in the rigidity of glasses with an increase in the concentration of CuO.