Broad-wave reflection of polymer-stabilised cholesterol liquid crystal with nanofibers doped magnetic nanoparticles

In this study, the polymer-stabilised cholesterol-based liquid crystal (PSCLC) films with broad-wave reflection were prepared via PVA nanofibers as carriers loaded with Fe3O4 nanoparticles. Fe3O4 nanoparticles have absorption properties in the UV region. When UV light is irradiated along the thickness of the liquid crystal cell, the resulting gradient distribution of UV light intensity induces a gradient distribution of spacing and thus a broad-wave reflection. Specifically, the effects of nanoparticles content loaded in nanofibers, magnetic field strength, polymerisation time and temperature, UV light intensity and polymerised monomer content were studied. The result shows that the proper contents of Fe3O4 nanoparticles and the polymerisation conditions have favourable impacts on the broad-wave reflection of PSCLC films. To clarify the mechanism of formed broad-wave reflection, the morphology of nanofibers was observed by scanning electron microscopy (SEM). The modification of nanoparticles was collected by transmission electron microscopy (TEM) and infrared spectroscopy. The texture of PSCLC films was observed by POM. The broad-wave reflection were measured by UV-Vis spectrophotometer. This strategy broadens the broad-wave reflection of PSCLC films from 300 nm to 476 nm increasing its application potential in UV shielding devices, and infrared thermal control devices.