Ultrastable structure and luminescence properties of Y2O3 nanotubes

Pure and Eu-doped Y 2O3 nanotubes (NTs) were synthesized by a hydrothermal method. The crystal structure of synthesized pure and Eu-doped Y 2O3 NTs are respectively stable to 22 and 18.3 GPa, which are about 10 GPa higher than bulk Y 2O3. Phase transformation routes of Y 2O3 NTs are cubic → amorphous directly instead of cubic → monoclinic → hexagonal of bulk Y 2O3. Due to the doped Eu3+ ions, the Eu-doped Y 2O3 has larger cell parameters, lower phase transformation pressure, and smaller bulk modulus compared to pure Y 2O3 NTs. The much elevated structural stability of the Eu-doped Y 2O3 NTs, which is attributed to the size-induced high energy kinetic hindrance, leads to an ultrastable luminescence. Such a novel property of Eu-doped Y 2O3 NTs is expected to play a significant role in high-stability nano-photo-devices.