Hydrothermal synthesis of nanostructured Y2O3 and (Y0.75Gd0.25)2O3 based phosphors

• Elongated particles of (Y1.25Gd0.75)2O3:Eu3+ and Y2O3:Yb3+/Er3 were successfully synthesised by the hydrothermal method.
• Effect of annealing time and temperature is correlated with the particles structural and morphological characteristics.
• Preferential dopants accommodation at C2 site position of Ia-3 structure was achieved in all annealed samples.
• Enhanced down and up-conversion, color tuning and superior decay times were established with change of Yb3+/Er3+ ratio.

Examples of (Y2O3–Gd2O3):Eu3+ and Y2O3:(Yb3+/Er3+) rare earth oxide-based phosphors are presented to highlight the controlled synthesis of 1D and 2D nanostructures through simple hydrothermal method. Conversion of the starting nitrates mixture into carbonate hydrate phase is performed with the help of ammonium hydrogen carbonate solution during hydrothermal treatment at 200 °C/3 h. Morphological architectures of rare earth oxides obtained after subsequent powders thermal treatment at 600 and 1100 °C for 3 and 12 h and their correlation with the optical characteristics are discussed based on X-ray powder diffractometry, field emission scanning electron microscopy, infrared spectroscopy and photoluminescence measurements. Strong red and green emission followed by the superior decay times are attributed to the high powders purity and homogeneous dopants distribution over the host lattice matrix.