Effect of anisotropic MoS₂nanoparticles on the blue phase range of a chiral liquid crystal

Abstract

Liquid-crystalline blue phases are attracting significant interest due to their potential for applications related to tunable photonic crystals and fast optical displays. In this work a brief theoretical model is presented accounting for the impact of anisotropic nanoparticles on the blue phase stability region. This model is tested by means of high-resolution calorimetric and optical measurements of the effect of anisotropic, surface-functionalized MoS2 nanoparticles on the blue phase range of a chiral liquid crystal. The addition of these nanoparticles effectively increases the temperature range of blue phases and especially the cubic structure of blue phase I.

Blue Phase Range Widening Induced by Laponite Nanoplatelets in the Chiral Liquid Crystal CE8

“…In particular, the spherical nanoparticles have a tendency to increase the stability range of BPIII [4,5], whereas the anisotropic ones target mostly the ordered structure of BPI [9,10]. Here we report that a small amount of anisotropic laponite nanoplatelets can effectively increase the temperature stability range of BPI of a chiral liquid crystal.…”

“…The protocol of mixture preparation has been described in detail elsewhere [4,9]. After preparation the sample was immediately placed in a high-purity silver cell.…”

“…More recently, spherical [3][4][5][6][7][8] or anisotropic nanoparticles [8][9][10] have been exploited as stabilisation agents. In all these cases nanoparticles are surface-functionalised in order to achieve a homogeneous dispersion in the liquid crystal hosts [4][5][6].…”

Self-Organized 3D Photonic Superstructure: Blue Phase Liquid Crystal

“…Luckily, since the defects can act as potential wells in the system, these impurities are trapped spontaneously in the defects. In the past few years, candidates including nanoparticles [24][25][26] and polymer network [27] were demonstrated to stabilize BPs either experimentally or theoretically [28][29][30]. Such stabilization raises not only the tolerance of thermal variation to a higher level but also the electro-optic threshold of lattice deformation [25] and phase transition to the cholesteric phase [31].…”

Electro-optics of polymer-stabilised blue phase liquid crystal in in-plane switching mode

“…Other techniques for BP stabilisation involve T-shaped molecules, [20] binaphthyl derivatives, [21,22] bent-shaped molecules, [23] hydrogen-bonded selfassembled complexes [24] and nanoparticles. [25][26][27][28][29][30][31] Coles and co-workers reported a dimeric LC having large flexo-electric coefficient and extended the BP range to 44 K. [32] PS-BPLC seems to be most promising but high onstate voltage (V on ), hysteresis, residual transmittance and long-term stability are a few remaining challenges yet to be resolved. The practical applications of BPs are limited due to hysteresis effect and many groups are actively engaged to meet this challenge.…”