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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. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu(I) complexes with polyaromatic substituents are synthesized and characterized. • The photophysical properties of the corresponding complexes is studied. • Extended π system has important influence on the light absorption abilities. • DFT/TDDFT methods were employed to understand the photophysical properties. The three Cu(I) complexes [Cu(POP)(N^N)]PF 6 , N^N = 2-(1 H -imidazol-2-yl)-5-(naphthalen-2-ylethynyl)pyridine (P1), 2-(1 H -imidazol-2-yl)-5-(phenanthren-9-ylethynyl)pyridine (P2), 2-(5-(naphthalen-2-ylethynyl)pyridin-2-yl)-1 H -phenanthro[9,10- d ]imidazole (P3), were prepared and characterized. The photophysical properties of these Cu(I) complexes is tuned by extending π- system of the N^N ligand through the addition of polyaromatic groups such as naphthalene and phenanthrene into the pyridine ring part of the diimine ligands via an acetylide linker or phenanthrene-fused imidazole ring. The resulting complexes exhibit higher absorption ability in the visible region. The emissions are in the range of 582–601 nm with quantum yields of 2.30–7.70% and the excited lifetimes of 77.4–115.8 μs for all complexes at room temperature. The photophysical properties were further explained by DFT and TDDFT methods. [ABSTRACT FROM AUTHOR]