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Rare Earth substituted Sesquioxides compounds, specially Yttria (Y2O3) are essential ceramic materials for solid-state lasers, light-emitting diodes, microchip lasers, and infrared detectors. In the present work, Ytterbium (Yb3+) substituted Y2O3 (Y2−xYbxO3, where, x = 0.0, 0.04, 0.08 and 0.12) ceramics are synthesized using co-precipitation method. The prepared samples were examined for structural, morphological and opto-electrical properties. The X-ray diffraction pattern shows the cubic phase for pure Y2O3 and mixed phase (cubic + monoclinic) for Yb3+doped Y2O3 ceramics. The lattice parameters initially decreases and then slightly increases with the incorporation of Yb3+ ions in Y2O3. Field-emission scanning electron microscopy demonstrate the morphological changes with varying particle size from 41 to 82 nm. The presence of Yb3+ ions in Y2O3 nanopowders have been additionally confirmed by XPS analysis. The optical studies dispaly a strong absorption between 200 and 360 nm with maximum bandgap value of 4.77 eV. The photoluminescence spectra shows characteristic peaks of violet, indigo, blue and green emission at 380 nm, 422 nm, 486 nm and 527 nm respectively. The dielectric constant and dielectric loss were observed to decrease with increasing frequency at room temperature. [ABSTRACT FROM AUTHOR]

In the present work, the authors have studied double doping of Rare Earth Elements (Nd3+, Er3+) into the lattice of Y 2 O 3 ceramic in the presence of sintering additives ZrO 2 +La 2 O 3 having formula (Y 0.915-x Zr 0.02 La 0.06 Nd 0.005 Er x) 2 O 3 where x= (0.5, 1.0, 1.5 at. %). The samples are synthesized using co-precipitation method. X-ray diffraction results reveals the formation of Y 2 O 3 structure having cubic unit cell and matched with JCPDS card No. 41-1105. A gradual shift towards higher angle side at 2θ = 29.2° has been observed with variation in Er doping. The particle size varied from 123 nm to 52 nm with doping and has a homogenous distribution. The presence of different dopants have been confirmed by XPS. The powder mixture was sintered at 1700 °C for 10hrs in an inert atmosphere, though resulting in translucent pellets when measured in the range of 200–2200 nm, due to non-uniform heating and different grain size. Under the excitation of 350 nm, the samples emitted blue, green, violet and indigo colours wavelengths, confirming transition from 4F 11/2 orbitals and their band gap also decreases from 5.2 eV to 4.80 eV. The sintered samples presented a dielectric constant of 15, which goes up to 18 upon increasing the concentration of Er. These results demonstrated the correlation and the effect of double doping on Y 2 O 3 for its opto-electronic applications. [ABSTRACT FROM AUTHOR]