X-ray diffraction study of the phase and morphology changes in yttrium compound nanoparticles

In the present experimental study, the precipitation of basic yttrium nitrate from aqueous solutions allowed the optimization of conditions for the preparation of loosely aggregated Y$_{2}$(OH)$_{5}$NO$_{3}$ $\cdot$ 1.5H$_{2}$O, the thermal decomposition of which, under controlled annealing, permitted the synthesis of yttria nanoparticles with desirable microstructure. The latter material can be widely used to manufacture yttria optical ceramics. Y$_{2}$(OH)$_{5}$NO$_{3}$ $\cdot$ 1.5H$_{2}$O thermolysis occurs via the formation of a metastable hexagonal Y$_{2}$O$_{3}$ based phase (a = 8.04, c = 12.37 $\mathring{\mathrm{A}}$).