Eu3+ addition effect on the stability and crystallinity of fiber single crystal and nano-structured Y2O3 oxide

Nano-structured powders and fiber single crystals of cubic yttrium oxide undoped and Eu2O3 doped with luminescent properties were prepared using two techniques. The first one is focused on direct oxide precipitation at low temperature in which europium-doped yttrium oxide (Y2O3:Eu3+) particles sizes less than 5 nm were synthesized in colloidal solution, followed by a controlled precipitation to obtain fine sub-micrometric powders. The second method is based on fiber single crystal growth using laser-heated pedestal growth (LHPG) and CO2 laser beam as heating source at 10.6 μm and homogeneous starting rod materials obtained from the synthesis of nano-scale materials. The fibers grown by LHPG technique were single crystal, transparent, homogeneous, red color when Eu3+ concentration is high. The crystal fiber quality decreases with increasing Eu3+ concentration higher than 2% because of segregation problem. The materials obtained by the soft chemistry are cubic and lies in the nano-meter range. The purity of the materials, europium concentration limit, particles sizes and structure were obtained from X-ray powders diffraction at room temperature. The segregation coefficient of Eu3+ is measured from EPMA analysis. The morphology of the materials was obtained using SEM. The luminescence of Eu3+ has been detected by excitation at λ=254nm.