Effect of the magnetic nanoparticle concentration on the electro-optical properties of the polymer-dispersed liquid crystals

ABSTRACT

In this paper, we investigated the electro-optical properties of the dilute magnetic polymer dispersed liquid crystals (PDLCs) prepared with the liquid crystal colloids containing low concentrations of γ-Fe₂O₃ nanoparticles. The doped nanoparticles have hardly changed the morphology of PDLCs, but they have significantly changed the threshold voltage, saturation voltage, and contrast ratio of PDLCs. Such changes result from ionic adsorption in competition with the concentration of the nanoparticles. When the concentration of the nanoparticles was below the critical concentration, the adsorption of free ions was dominant, and the contrast ratio increased while the saturation voltage decreased. However, when the concentration of the nanoparticles was above the critical concentration, the intrinsic electro-optical effect of the nanoparticles was dominant, and the contrast ratio decreased while the saturation voltage increased.

KEYWORDS:

• Liquid crystals
• nanomaterials
• γ-Fe₂O₃ nanoparticles
• dilute magnetic PDLC

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

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Additional information

Funding

This work is supported by Fundamental Research Funds for the Central Universities (grant number 2021YJS143), the Doctoral Foundation of Southwest University (grant number SWU115010), Natural Science Foundation of Chongqing, China (grant number cstc2021jcyj-msxmX1136), National Natural Science Foundation of China (grant number 51735006, U1837206, 51927810), and Beijing Municipal Natural Science Foundation (grant number 3182013)