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A single-layer polymer stabilized liquid crystal (PSLC) film reflecting both right- and left-circularly polarized light has been developed by a wash-out/refill method. The PSLC film was achieved by prefabricating the polymer network with a left-handed helical structure and then refilling a cholesteric liquid crystal with a right-handed helical structure into the network. The reflection intensity of the PSLC film is close to 100% when the pitch lengths of the two opposite helical structures are the same. It was demonstrated that the memory effect of the polymer network is an important mechanism for the resulting film properties.

Efficiently luminescent composite fibers of poly (vinyl pyrrolidone) (Mw≈1300000) and europium complex Eu(TTA)3(TPPO)2 (TTA is thenoyltrifluoroacetone; TPPO is triphenylphosphine oxide) were prepared by electrospinning, with average diameters of 200–500nm and lengths of several tens of micrometers. Their photoluminescence properties were studied in comparison to the pure Eu(TTA)3(TPPO)2 complex. It was significant to observe that the thermal stability of photoluminescence in the composite fibers was improved considerably over the pure complex.

Europium-doped yttria nanotubes were coated with yttria by a simple two-step hydrothermal method, forming the Y2O3:Eu3+∕Y2O3 core-shell composite. Remarkable improvement of photoluminescence was observed in the core-shell composite under both violet and ultraviolet excitations. These characteristics were attributed to the reduced influence of surface defects on host excitation, charge transfer transitions, and f−f inner-shell transitions of the Eu3+ ions. Due to striking red luminescence under ultraviolet excitation, the core-shell structure has potential application in plasma display panel devices.