Cutting edge development on graphene derivatives modified by liquid crystal and CdS/TiO₂ hybrid matrix: optoelectronics and biotechnological aspects

Abstract

Two dimensional (2D) graphene and its derivatives modification with nanomaterials for formation of hybrid/nanocomposites undergo stimulus-induced optical and electrical changes which are important for many new switchable device technologies. The feature article deals with a straight forward and versatile technique for the fabrication of semiconductor nanomaterials (CdS and TiO₂) nanomaterials dispersed liquid crystals (NDLC) or graphene dispersed liquid crystal (GDLC) by stretching hydrogen bonds (H-) in the precursor droplets between two substrates to form a liquid bridge. Fewer liquid crystals (LCs) possess a conventional oriented nematic phase with optimal performances. Evolving advantages of thin-film nanocomposite materials and switchable devices have fueled several developments in the field of flexible electronics, high contrast ratio smart display and opto-electronics. These advantages have been complemented with the expansion of novel composite materials such as GDLC and NDLC as sensors to monitor the inflammability, explosive nature and toxicity of chemicals. This discussion also delves into the fabrication of graphene assembly polymer nanocomposites dispersed in LCs, the necessity for bio-polymer incorporation and their bio-sensing and antimicrobial applications. Additionally, discussed the issues and challenges associated with understanding and exploiting the potentials of smart switchable devices fabricated by nanomaterials or polymer/graphene hybrid composite matrix. Following substantial development and optimized over decades, a novel mechanism employed in smart switchable devices via GDLC hybrid nanocomposite matrix has been found to offer numerous benefits including being cost-effective, possessing a large area compatibility and large scalability in addition to seamless heterogeneous integration.

Keywords:

• Graphene
• nanomaterials
• liquid crystal
• nanocomposite
• switchable device
• biological application

Acknowledgments

The author Dr. Kaushik Pal is grateful to associate with colleagues and research scholars at IIUCN, School of Chemical Sciences and Energy Materials research division at Mahatma Gandhi University, Kottayam (Kerala). Dr. Kaushik Pal especially owes his sincere thanks to his colleagues including doctoral and postdoctoral scholars consistent effort, instrumental operators, as well as an entire team of researchers are also gratefully acknowledged to Vice-Chancellor (Prof. Sabu Thomas) support at School of Chemical Sciences, MG University. The author Dr. Gharieb S. El-Sayyad would like to thank the Nanotechnology Research group of Dr. Ahmed I. El-Batal), NCRRT (Egypt).

Conflict of interests

All the authors have declared that, there is no conflict of any financial interests or authorship to publish the article.