Morphological, dielectric, electro-optic and photoluminescence properties of titanium oxide nanoparticles enriched polymer stabilized cholesteric liquid crystal composites

Herein, TiO2 nanoparticles (NPs) dispersed polymer stabilized cholesteric liquid crystal (PSCLC) composites are prepared and studied. Effect of TiO2 NPs doping in varying concentration into PSCLC, on the phases, molecular states, dielectric, electro-optic and photoluminescence properties are investigated in studied samples. The morphological studies reveal that the TiO2 NPs are responsible to switch the orientation of liquid crystal molecules into homeotropic state at a lower voltage. The permittivity reduced from 9.62 to 7.75 at an optimum doping amount (0.5 wt%) of TiO2 NPs. At this concentration, an improvement in dielectric anisotropy was found. A decrease in threshold voltage from 3.2 V to 1.4 V was observed. Further, the saturation voltage also decreases from 10.5 V to 7.5 V at 0.5 wt% doped TiO2 NPs. The photoluminescence intensity increase with TiO2 NPs concentration however emission wavelength does not change. This work may provide a facile approach to fabricate the low energy consumption based electro-optical devices with the affordable and eco-friendly nature of TiO2 NPs.