Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8160923 | Physica B: Condensed Matter | 2018 | 26 Pages |
Abstract
Sodium niobate (NaNbO3) ceramics is prepared by conventional solid state reaction method at sintering temperature 1150â¯Â°C for 4â¯h. The structural information of the material has been investigated by X-ray diffraction (XRD) and Field emission scanning electron microscopy (FE-SEM). The XRD analysis of NaNbO3 ceramics shows an orthorhombic structure. The FE-SEM micrograph of NaNbO3 ceramics exhibit grains with grain sizes ranging between 1â¯Âµm to 5â¯Âµm. The surface coverage and average grain size of NaNbO3 ceramics are found to be 97.6 % and 2.5â¯Âµm, respectively. Frequency dependent electrical properties of NaNbO3 is investigated from room temperature to  500â¯Â°C in wide frequency range (100â¯Hz-5â¯MHz). Dielectric constant, ac-conductivity, impedance, modulus and Nyquist analysis are performed. The observed dielectric constant (1â¯kHz) at transition temperature (400 °C) are 975. From conductivity analysis, the estimated activation energy of NaNbO3 ceramics is 0.58â¯eVâ¯at 10â¯kHz. The result of Nyquist plot shows that the electrical behavior of NaNbO3 ceramics is contributed by grain and grain boundary responses. The impedance and modulus spectrum asserts that the negative temperature coefficient of resistance (NTCR) behavior and non-Debye type relaxation in NaNbO3.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
Abhinav Yadav, Snigdha Paramita Mantry, Mohd. Fahad, P.M. Sarun,