Novel composite nanomaterials with superior thermal and pressure stability for potential LED applications.

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]