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The objective of this research is to develop perovskite compounds with electrical and dielectric properties that can be used in technological applications including magnetism, health, and electronic devices. Polycrystalline of double perovskite BiBa0.5Ag0.5Ni2O6 was successfully synthesized by sol–gel method. Preliminary X-ray investigation established at room temperature the formation of compound with rhombohedral structure of the R 3 ¯ C space group. The uniform grain distribution and chemical composition are predicted from the scanning electron microscope and energy-dispersive X-ray technique, which has an average grain size of 563 nm. Electrical properties electrical depends on temperature and frequency. Impedance spectroscopy and electrical modulus of the compound were analyzed by impedance analyzer in the range of frequency (1 kHz–1 MHz) and temperature (200–400 K) that confirmi non-Debye type of relaxation. In addition, the frequency dependence of the electrical conductivity of material prepared at different temperatures was studied using Jonscher's law. The conduction and relaxation mechanisms remain same in the entire temperature range. From these results, it may be concluded that this compound may have extreme potential applications at different temperatures, for example in the electrical field, in capacitors. [ABSTRACT FROM AUTHOR]

The structural, morphological, dielectric and electrical properties for BiBaNiNbO6 sample prepared by sol–gel method have been investigated in this work. X-ray investigation confirms the formation of single phase with rhombohedral crystal structure with space group R 3 ¯ C at room temperature. Energy dispersion spectroscopy (EDS) analysis and scanning electron microscopy were used to confirm the chemical make-up of the synthesized molecule and the morphology of the grain size (SEM). The Z″(f) curve confirms the appearance of a relaxation phenomenon in the sample which exhibits semiconductor behavior. An electrical circuit consisting of a link of grain and grain boundary elements is used to analyze the Nyquist plots between the ranges of 200 and 360 K and 100 Hz and 1 MHz, respectively. The variation of electrical conductivity at various temperatures obeys the Jonscher's power law. The Non-overlapping Small Polaron Tunneling (NSPT) is the appropriate model to explain the conduction mechanism for the sample. The estimated activation energies from the DC conductivity and electrical impedance are close implying that the relaxation and conduction processes are caused by the same type of charge carriers. Electrical and optical properties show higher electrical resistivity and considerable visible light absorption which makes the prepared BiBaNiNbO6 double perovskite suitable candidate for electrical applications. [ABSTRACT FROM AUTHOR]

In this paper, impedance spectroscopy, modulus analysis, AC electrical conductivity, and dielectric properties of double perovskite compound of general formula SrAgNiMnO6, synthesized by sol–gel method, have been reported in the temperature ranges (200–400 K) and frequency (1 kHz to 1 MHz). From the X-ray structural studies at room temperature, it is found that the material is single phase and their structure crystallizes in the rhombohedral system with the space group R 3 ¯ C . The morphology and grain size of the sample were observed using a scanning electron microscope (SEM), which clearly shows that the grains are uniformly distributed with few voids. By analyzing Nyquist diagrams, the existence of grain and grain boundary effects are established. The type of relaxation is non-Debye studied by the analysis of the complex impedance and modulus. We find that the resistances decrease with the increase in temperature indicating the semiconductor character of the material. The evolution of the AC conductivity with respect to the frequency obeys Joncher's law. Besides, the activations energies obtained from the conductivity and the imaginary part of the impedance are very close. The study of frequency dependence of the dielectric loss indicates a phenomenon of relaxation in our material. From these results, it can be concluded that this compound can have very important electrical and dielectric properties for different temperatures and frequencies. It can therefore be used in technological applications, for example, in the electrical field knowing that capacitors. [ABSTRACT FROM AUTHOR]