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A novel white-emitting ZnO@Eu 2 O 3 core/shell nanomaterials was synthesized by a green chemical method. The temperature and pressure dependence of the photoluminescence (PL) transition associated with the fundamental bandgap of ZnO@Eu 2 O 3 core/shell nanomaterials have been studied. The activation energy of ZnO@Eu 2 O 3 is 0.27 eV, which is higher than the commercial Y 2 O 3 : Eu 3+ . The near-bandedge emission is found to shift toward higher energy with applied pressure at a rate of 32.7 MeV/GPa with a small second-order term of −0.28 MeV/GPa 2 . The samples are very stable with white emission under 8 GPa, which are useful for white LEDs. [ABSTRACT FROM AUTHOR]

The structural, optical properties and catalytic activity of ZnO@Eu 2 O 3 core-shell nanostructutres have been investigated systematically. Sharp intense red emissions in the range of 580–650 nm due to the intra-4f transition of Eu 3+ ions are observed from the sample. It is found that some of the Eu 3+ ions are in the Eu 2 O 3 -like state located at the surface of ZnO and others are doped into ZnO host. Incorporation of Eu 3+ ions into a ZnO host resulted in deterioration in crystal quality and lattice distortion. Adding the Eu 2 O 3 layer increased the number of excited carriers within ZnO, thus enhancing the luminescence and photocatalysis properties. Our findings not only open an avenue for synthesis sophisticated ZnO@Eu 2 O 3 core-shell nanostructutres but also pave a way towards improving red emission and photocatalysis properties in ZnO nanostructures. [ABSTRACT FROM AUTHOR]