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Herein, a study on the dielectric properties of ZnO–P2O5–SeO2 glass ceramics containing varied contents of Ag2O is presented. Structural analysis of the samples by X‐ray diffraction, transmission electron microscopy, differential scanning calorimetry, Fourier transform infrared spectra, and optical absorption techniques indicated that the glasses are embedded with Ag3PO4, Ag2SeO3, and Zn3(PO4)2 anisotropic crystal phases along with Ag+ ions and Ag0 particles. Dielectric properties, ac conductivity (σac), and dielectric breakdown strength (DBS) are investigated as functions of Ag2O concentration. The results show the maximal concentration of Ag+ ions and Ag0 metallic particles in the sample containing 0.6 mol% of Ag2O. Dielectric parameters and (σac) increase with increasing Ag2O up to 0.6 mol%, while the DBS and electrical impedance decrease. The observed dipolar effects are quantitatively analyzed and possible dipoles are identified. Ionic contribution is predominant up to 0.6 mol% of Ag2O, beyond which the polaronic tunneling phenomenon prevails. These findings indicate that 0.6 mol% of Ag2O is the optimal concentration for using these glass ceramics as solid electrolytes in ionic batteries. Moreover, glass ceramics containing Ag2O beyond 0.6 mol% have exhibited larger polaronic conductivity, hence such glasses can be considered suitable candidates for electrodes in ionic batteries. [ABSTRACT FROM AUTHOR]

An exotic series of glasses with the composition 39PbO—(60–x)B2O3–xSeO2:1.0 Nd2O3 (10 ≤ x ≤ 50) is prepared and characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X‐ray spectroscopy (EDS) techniques. Results of infrared (IR), Raman, and X‐ray photoelectron spectroscopy (XPS) studies reveal that the glass network comprises quarantined selenite [SeO3]2− groups (that act as modifiers) and selenate [SeO4]2− groups in addition to BO3 and BO4 units. With the increase in SeO2 content, the concentration of selenite groups is found to be dominant. The optical absorption (OA) spectra exhibit several bands due to 4I9/2→2P1/2, 2G9/2, 4G9/2,7/2,5/2, 2H11/2, and 4F9/2, 7/2,5/2,3/2 transitions. The spectra are characterized using J–O theory and J–O parameters are found to follow the order: Ω2 > Ω6 > Ω4. The emission spectra recorded at λexc = 808 nm exhibit bands due to 4F3/2 → 4I9/2, 4I11/2, and 4I13/2 transitions. With increase in SeO2 content, intensity of all emission bands significantly increases. The quantum efficiency evaluated from the measured and calculated lifetimes of the 4F3/2 → 4I11/2 transition is found to be enhanced by 20% with increase in SeO2 from 10 to 50 mol%. The spectra are further analyzed quantitatively using kinetic rate equations of various excited levels and the reasons for enhancement of photoluminescence (PL) emission are identified and discussed. [ABSTRACT FROM AUTHOR]