Ion dynamics in lithium bismuth borate conducting glasses have been reported in wide composition and temperature ranges. The activation energy for the dc conduction has been analysed using Anderson-Stuart model and a correlation between the dc conductivity and the doorway radius has been predicted. The characteristic length scales for ion dynamics, such as mean square displacement and spatial extent of sub-diffusive motion of lithium ions have been determined from the ac conductivity and dielectric spectra, respectively. A direct connection between the ion dynamics and the characteristic length scales and the network structural units have been established.

We have studied the mixed network former effect on the dynamics of lithium ions in borotellurite glasses in wide composition and temperature ranges. The length scales of ion dynamics, such as characteristic mean square displacement and spatial extent of sub-diffusive motion of lithium ions have been determined from the ac conductivity and dielectric spectra, respectively, in the framework of linear response theory. The relative concentrations of different network structural units have been determined from the deconvolution of the FTIR spectra. A direct correlation between the ion dynamics and the characteristic length scales and the relative concentration of BO4 units has been established for different compositions of the borotellurite glasses.

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Nanoparticles of Ni0.3Zn0.4Ca0.3Fe2O4 (NZCF) were successfully prepared by the facile wet chemical method coupled with the sonochemical method. These nanoparticles were embedded in a graphene oxide (GO) matrix (NZCFG). Rietveld analyses of X-ray diffraction, transmission electron microscope, scanning electron microscope, and X-ray photoelectron spectroscopy were carried out to extract different relevant information regarding the structure, morphology, and ionic state. A major improvement in saturation magnetization is achieved due to substitution of Ca2+ in the ferrite lattice. Interestingly, the observed value of electromagnetic absorption for a sample thickness of 1.5 mm is ∼−67.7 dB at 13.3 GHz, and the corresponding bandwidth is 5.73 GHz. The Cole–Cole plot, the Jonscher power-law fitting, and the Nyquist plot confirm the probability of improved hopping conductance and attractive capacitive behavior in NZCFG. The presence of magnetic energy morphing in combination with a higher attenuation constant, lower skin depth, and various forms of resonance and relaxation makes NZCFG the most suitable for microwave absorption.

We have studied the dynamics of silver ions in AgI-doped AgO-SeO-MoO mixed former glasses in wide frequency and temperature ranges. We have observed that the ionic conductivity exhibits a mixed glass network former effect for low AgI content. The scaling for the conductivity spectra shows that the mechanism of charge carrier dynamics is independent of temperature and composition. We have obtained a mobile Ag ion concentration from the Nernst-Einstein relation, which is found to be independent of temperature, but slightly dependent on composition. We have also obtained the characteristic mean square displacement of the silver ions from the mapping of the conductivity spectra in the time domain. It is observed that the composition dependence of the characteristic displacement is opposite to that of the conductivity. We have also studied the influence of the network structure of these glasses on ion dynamics using infrared spectra and established a correlation between the ion dynamics and the SeO structural units. It is observed that the available hopping sites for Ag ions increase in the glass network with the increase of non-bridging oxygens of SeO units.