Effect of cobalt oxide nanoparticles on dielectric properties of a nematic liquid crystal material

 

Recently nanoparticles (NPs) are extensively explored as the dopant in liquid crystal (LC) materials because of their phenomenal properties such as good guest–host interaction and high surface to volume ratio. Keeping this motivation into mind, we have observed the influence of newly synthesized cobalt oxide (CoO) NPs on the dielectric and optical properties of nematic LC (NLC) namely 5 CB. For the observation of dielectric properties, we have performed dielectric spectroscopic measurements in the frequency range from 20 Hz to 1 MHz. The sample cell thickness-dependent studies have been performed to perceive the effect of applied field strength on dielectric parameters in presence of CoO NPs. Along with it, we have observed the alignment of the mesogens through the optical microscopy. So doping of such NPs serves various potential applications in the field of research as well as being proven to be cost-effective for industrial applications.

In this article, we report the variation in dielectric properties of nematic liquid crystal (NLC) namely 5CB by the means of cobalt oxide nanoparticles (CoO NPs) doping. These CoO NPs may work as the ion absorbing agent in the NLC medium and can easily modify dielectric properties without influencing molecular alignment. Along with this, we have performed the LC sample cell thickness dependent studies of pure and CoO NPs doped 5 CB.

KEYWORDS:

• Dielectric properties
• nematic liquid crystals
• cobalt oxide nanoparticles

Acknowledgement

The authors sincerely thank Dr. Arham Shareef Ahmed, Assistant Professor, Department of Physics, Aligarh Muslim University, Aligarh to provide CoO NPs for the purpose of doping. The authors are also thankful to Ms. Jhalak Gupta for her fruitful discussions.

Additional information

Funding

The author Depanshu Varshney would also like to thank Department of Science and Technology (DST), India to provide INSPIRE fellowship for the sake of financial support. One of the authors Dr. Jai Prakash is grateful to the Department of Science and Technology (DST) for supporting this work under the Science and Engineering Research Board (SERB) funded EMR Project (EMR/2016/006142).