Articles written in Bulletin of Materials Science

    • Microstructure, spectral and frequency dependent electrical studies of Ni-and Zn-substituted Co$_3$O$_4$ spinels for capacitor applications


      More Details Abstract Fulltext PDF

      Substituted Co$_3$O$_4$ spinels in the form of NiCo$_2$O$_4$ and ZnCo$_2$O$_4$ are prepared by a wet chemical co-precipitation approach at 500°C. The average grain size of substituted Co$_3$O$_4$ spinels is estimated from scanning electron micrographs and projected to be typically below 200 nm. Furthermore, microstructure analysis illustrates the ability of Ni and Zn substituents as an effective grain growth facilitator for Co$_3$O$_4$ spinel. Fourier transform infrared spectrum for all prepared spinels shows the prominent peaks corresponding to metal-oxide stretching vibration suggestive of pure phase formation. The electric and dielectric properties of substituted Co$_3$O$_4$ spinels were studied in the frequency range of 40 Hz to 8 MHz at different temperatures. For all spinels, the giant relative permittivity notably reduces with the increment in frequency and remains nearly same in higher frequencies at all temperatures. Conversely, the ac-conductivity remains almost same throughout studied frequencies but enhances with temperature, a behaviour typically observed in negative temperature co-efficient thermostats. The increase in tan ${\delta}$ as a function of temperature and complex impedance behaviour also endorses the conduction mechanism.

  • Bulletin of Materials Science | News

    • Dr Shanti Swarup Bhatnagar for Science and Technology

      Posted on October 12, 2020

      Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
      Chemical Sciences 2020

      Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
      Physical Sciences 2020

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2022-2023 Indian Academy of Sciences, Bengaluru.