Solvent interface effect on the size and crystalline nature of the GdPO4:Eu3+ nanorods.

GdPO 4 :Eu 3+ nanorods (~20 nm) were synthesized by a facile hydrothermal technique based on the water/2-PrOH interface. The size of nanorods was controlled by varying the reaction temperature and solvent interface. After calcination at 700 °C, the hexagonal phase of as-prepared GdPO 4 ·H 2 O:Eu 3+ nanorods was transformed into the monoclinic phase, which was confirmed by XRD patterns and TEM images. During the calcination process, along with the phase transformation, the size of nanorods was also shortened by the removal of H 2 O molecules from the lattice. Photoluminescence (PL) excitation spectra revealed the efficient energy transfer between Gd 3+ and Eu 3+ ions and the orange-red emission was typically observed from PL spectra because the Eu 3+ ions exist with inversion symmetry in the lattice. Also, these GdPO 4 :Eu 3+ nanorods were highly dispersible in water. [ABSTRACT FROM AUTHOR]