The influence of the size of harvested barium titanate nanoparticles on the properties of ferroelectric liquid crystal (FLC) nanocolloids was investigated by electro-optical and dielectric methods. The spontaneous polarization and the switching time are decreased for the liquid crystalline nanocolloids compared to nondoped FLC mixtures of different dipole strengths; this dependence is stronger for small size particles (9 nm) and weaker for larger size particles (26 nm) by the same concentration in weight. The decrease of the Goldstone mode (GM) relaxation frequency and the decrease of the dielectric GM absorption strength of the nanocomposites compared to the nondoped FLC mixture go stepwise with the increase of the nanoparticles diameter. Results have been interpreted via strong interaction between the FLC dipoles and the dipoles of the highly polar barium titanate nanoparticles.

The influence of gold nanoparticles dispersed in ferroelectric liquid crystals (FLCs) on the properties of the resulting nanocolloids has been investigated by thermoanalytical, electrooptical and dielectric methods. All gold nanoparticles were protected by thiolate capping layers either connected via alkyl groups of different chain length or via flexible spacers bridged to liquid crystalline p-cyano-biphenyl end groups. The colloidal stability of the gold nanocomposites with capping layers consisting of nonyl or octadecylthiolate groups is drastically reduced compared to the stability of those with p-cyanobiphenyl end groups. The present work describes the influence of the kind of capping layers around the gold nanoparticles and the effect of the amount of gold nanoparticles dispersed in such liquid crystal colloids on their electrooptical and dielectric parameters.

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