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Nano Research 2017, 10(2): 618-625 https://doi.org/10.1007/s12274-016-1321-5
Research Article | Issue | Published: 01 December 2016

Effects of morphology and concentration of CuS nanoparticles on alignment and electro-optic properties of nematic liquid crystal

Show Author's Information Bin Liu,  Yiran Ma,  Dongyu Zhao( ),  Lihong Xu,  Fashun Liu,  Wei Zhou( ),  Lin Guo( )
Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology, Ministry of Education, School of Chemistry and Environment, Beihang University, Beijing 100191, China
Keywords:
vertical alignment, liquid crystal, CuS nanoparticles, electro-optic properties
Cite this article:
Liu B, Ma Y, Zhao D, et al. Effects of morphology and concentration of CuS nanoparticles on alignment and electro-optic properties of nematic liquid crystal. Nano Research, 2017, 10(2): 618-625. https://doi.org/10.1007/s12274-016-1321-5
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Abstract Full text Electronic supplementary material About this article

Nanoparticles (NPs) with flower-like and frame morphologies were synthesized from CuS, a remarkable transition-metal sulfide. We introduced two kinds of CuS NPs into a nematic liquid crystal (LC) 4-cyano-4'-n-pentylbiphenyl (5CB) and investigated the morphology- and concentration-dependent alignment and electro-optic (E-O) effects of CuS NPs on 5CB. A trace amount of flower-like CuS NPs induced a uniform homeotropic orientation of LC molecules; this is attributable to the obtained desirable compact nanosheet structure. Moreover, both flower-like and frame CuS NPs induced a remarkable improvement in the E-O properties of 5CB, and the flower-like CuS/5CB system exhibited a better performance. The doped CuS NPs in the LC host suppressed the shielding effect and strengthened the electric field, resulting in outstanding E-O properties. At a doping concentration of 0.05 wt.%, CuS NPs were well-dispersed and achieved the optimum E-O performance. This study provides a novel method for inducing a uniform orientation and enhanced E-O properties of LC molecules by doping with extraordinary CuS NPs, leading to potential applications in establishing flexible LC displays.


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Electronic supplementary material
About this article

Effects of morphology and concentration of CuS nanoparticles on alignment and electro-optic properties of nematic liquid crystal

Show Author's information Bin Liu, Yiran Ma, Dongyu Zhao( ), Lihong Xu, Fashun Liu, Wei Zhou( ), Lin Guo( )
Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology, Ministry of Education, School of Chemistry and Environment, Beihang University, Beijing 100191, China

Abstract

Nanoparticles (NPs) with flower-like and frame morphologies were synthesized from CuS, a remarkable transition-metal sulfide. We introduced two kinds of CuS NPs into a nematic liquid crystal (LC) 4-cyano-4'-n-pentylbiphenyl (5CB) and investigated the morphology- and concentration-dependent alignment and electro-optic (E-O) effects of CuS NPs on 5CB. A trace amount of flower-like CuS NPs induced a uniform homeotropic orientation of LC molecules; this is attributable to the obtained desirable compact nanosheet structure. Moreover, both flower-like and frame CuS NPs induced a remarkable improvement in the E-O properties of 5CB, and the flower-like CuS/5CB system exhibited a better performance. The doped CuS NPs in the LC host suppressed the shielding effect and strengthened the electric field, resulting in outstanding E-O properties. At a doping concentration of 0.05 wt.%, CuS NPs were well-dispersed and achieved the optimum E-O performance. This study provides a novel method for inducing a uniform orientation and enhanced E-O properties of LC molecules by doping with extraordinary CuS NPs, leading to potential applications in establishing flexible LC displays.

Keywords: vertical alignment, liquid crystal, CuS nanoparticles, electro-optic properties

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Publication history
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Acknowledgements

Publication history

Received: 30 July 2016
Revised: 08 October 2016
Accepted: 08 October 2016
Published: 01 December 2016
Issue date: February 2017

Copyright

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2016

Acknowledgements

Acknowledgements

This work was supported by the National Natural Science Foundation of China (Nos. 51203005 and 51673008).

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