Dielectric study of gold nanoparticle doped polymer dispersed liquid crystal

In the present work, we prepared gold nanoparticle (GNPs) doped polymer dispersed liquid crystal (PDLC) composite by dispersing 1% (wt./wt.) citrate buffer stabilized gold nanoparticles (GNPs) into a polymer and liquid crystal (LC) by polymerization induced phase separation technique. The effect of GNPs on the dielectric relaxation behavior of the PDLC composite is studied in 20 Hz to 10 MHz region. The real and imaginary part of permittivity depicts decrease in the GNP-PDLC composite. Two relaxation peaks are seen in the GNP-PDLC composite whereas only one relaxation process is observed in the PDLC. The high frequency peak can be observed in the 1 MHz region while the low frequency relaxation peak can be observed specifically in the GNP-PDLC composite. The dielectric anisotropy is seen to increase in the GNP-PDLC composite. The temperature dependence of permittivity shows that the nematic-isotropic transition temperature slightly varies in the doped composites. The UV-Vis spectra of both composites depict that the band structure is unaltered in the GNP-PDLC composite.