Low temperature investigation on dielectric properties of carbon doped copper oxide

Abstract

Carbon-doped copper oxide (CuO)_{1 -x} C _x (x = 0, 0.05 and 0.1) samples were synthesized by solid state reaction method, and sintered at 850 °C for 12 h. An X-ray diffraction (XRD) result shows that the structure of the samples was monoclinic. Dielectric studies were carried for these samples in the temperature range 80 K − 300 K between the frequency range 20 Hz − 1 MHz via impedance analyzer. The permittivity and tangent loss values of the doped samples increase with increasing doping concentration. In AC conductivity study, the conductivity mechanism of the 0% and 10% carbon doped samples follows correlated barrier hopping (CBH) model and 5% carbon doped sample follows quantum mechanical tunnelling (QMT) model. The temperature-dependent conductivity curve seems to obey the Arrhenius behavior. The activation energy values have been calculated from the frequency-dependent conductivity curves. The cole–cole plot shows the formation of grain and grain boundary in the samples.

Keywords:

• Copper oxide
• permittivity
• AC conductivity
• activation energy
• cole–cole plot

Additional information

Funding

The authors (B. Hema Chandra Rao and A. Venkateswara Rao) would like to thank management of K L E F, Department of Science & Technology (DST), Govt. of India, for the award of DST-FIST level-I (SR/FST/PS-I/2018/35) to Department of Physics and also thank Principal and Management of Malla Reddy Engineering College (Autonomous) for providing facilities. This work is financially supported by the Department of Science and Technology (DST), Science and Engineering Research Board (SERB), Govt. of India, New Delhi, under Young Scientist Project no.: SB/FTP/ETA-0176/2014 (AV Rao); and ECR/2016/001647 (GN Rao).