Effect of surfactant concentration and solvent used for washing in the preparation of $\mathrm{Yb}:\mathrm{Y}_2\mathrm{O}_3$ transparent ceramics

Nanoparticles of $\mathrm{Yb}:\mathrm{Y}_2\mathrm{O}_3$ have been synthesized by coprecipitation synthesis routes. The $(\mathrm{NH}_4)_2\mathrm{SO}_4$ surfactant was added to $\mathrm{Y}(\mathrm{OH})_3$ precipitate during synthesis to control the size, morphology, agglomeration and phase of nanoparticles. The dried precipitates were calcined at $900^\circ$ C to obtain the desired cubic phase $\mathrm{Yb}:\mathrm{Y}_2\mathrm{O}_3$ nano particles. In the present study we reported the effects of surfactant concentration on size, morphology, agglomeration and phase of $\mathrm{Yb}:\mathrm{Y}_2\mathrm{O}_3$ nanoparticles. However the addition of surfactant is not enough to get non-agglomerated nanoparticles. The extracted precipitate should be washed in proper solvent to avoid formation of hard agglomerate during drying. Hence the effects of washing solvent (i.e. water and methanol) on agglomeration and transparency were also reported. The transparency of the sintered pellets, prepared by varying the surfactant concentration and washing solvent, was evaluated. A transparency of $\sim80$ % at $1500$ nm was achieved in $1$ mm thick $\mathrm{Yb}:\mathrm{Y}_2\mathrm{O}_3$ ceramic pellet by optimization of the surfactant and washing solvent.