Synthesis of Yttria Nanopowders by Two Precipitation Methods andInvestigation of Synthesis Conditions

Yttrium oxide nanopowder was successfully synthesized by two precipitation methods, through which Y2O3 nanopowder was prepared by ammonium hydroxide and ammonium hydrogen carbonate as precipitants. Hydroxide and carbonate precursors of Y2O3 with approximate composition of Y(OH)(3) and Y-2(CO3)(3), respectively, were synthesized using yttrium nitrate as the starting salt. XRD results show cubic yttrium oxide phase for annealed samples. SEM and TEM images show that samples are composed of agglomerated and nonagglomerated nanoparticles with different shapes and sizes. Optimal conditions for synthesis of nanoparticles were defined as 3-h aging time, ammonium hydrogen carbonate as precipitant, and calcination temperature of 1000 degrees C.