The effect of high dielectric BaTiO3 nanoparticle dimensions on the dielectric properties and electro-optical performance of polymer dispersed liquid crystal films

To address the challenge of high switching voltages in polymer dispersed liquid crystal (PDLC) films, BaTiO3 nanoparticles of various dimensions were incorporated into a PDLC matrix. This study utilized a polymerisation-induced phase separation (PIPS) method, employing a UV curable photopolymer (NOA65), nematic liquid crystals (E7), and BaTiO3 (BTO) nanoparticles in zero-dimensional (0-BTO), one-dimensional (1-BTO), and two-dimensional (2-BTO) forms. The integration of different dimensional BTO nanoparticles significantly influenced the dielectric properties of the PDLC films, as demonstrated by the micro-morphology and electro-optical performance analysis. Notably, the incorporation of 1-BTO nanoparticles resulted in the lowest saturation voltage of 17 V, a 58% reduction, attributed to the increased dipole moment. Additionally, the introduction of 1-BTO nanoparticles did not compromise the transmittance and long-term cycling stability of the PDLC films.