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) compos-ites 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 orien-tation 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 improve-ment 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 wave-length 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. (c) 2023 Elsevier B.V. All rights reserved.

Automated summary

TiO2 nanoparticles dispersed polymer stabilized cholesteric liquid crystal (PSCLC) composites were prepared and studied. The effects of TiO2 NPs doping on the properties of the samples including phases, molecular states, dielectric, electro-optic, and photoluminescence properties were investigated. The morphological studies showed that TiO2 NPs could switch the orientation of liquid crystal molecules into a vertical state at a lower voltage. The permittivity decreased and the dielectric anisotropy and the threshold and saturation voltage improved with the doping of 0.5 wt% TiO2 NPs. The photoluminescence intensity increased with TiO2 NPs concentration but the emission wavelength remained unchanged. This work provides a facile approach to fabricate low energy consumption based electro-optical devices with affordable and eco-friendly nature of TiO2 NPs.