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The fabrication peculiarities of low-agglomerated yttria(Y2O3) nanopowders via thermal decomposition of sulfate-doped precursor with transient morphology were studied.It was determined that Y2(OH)5(NO3)x(CO2)y(SO4)z·nH2O(n=1–2) crystalline precursor underwent fragmentation and decomposition into isolated quasi-spherical Y2O3 particles upon calcination.Effect was connected with minimizing the free energy of the plate-like crystallites via reducing the contact surface until to the moment of spheroidization and attainment of isolation that occurred at Т=1100 °С.Residual sulfate ions slowed down the surface diffusion during heat treatment thus retaining quasy-spherical morphology and low aggregation degree of Y2O3 nanopowders.Sulfate-doped yttria nanopowders with medium particle size of 53±13 nm possessed improved sinterability in comparison with undoped ones arising from finer particle size,narrower particle distribution and lower agglomeration degree.
The fabrication of peculiarities of low-agglomerated yttria (Y2O3) nanopowders via thermal decomposition of sulfate-doped precursors with transient morphology were studied. It was determined that Y2 (OH) 5 (NO3) x (CO2) y (SO4) znH2O n = 1-2) crystalline precursor underwent fragmentation and decomposition into quasi-spherical Y2O3 particles upon calcination. Effect was connected with minimizing the free energy of the plate-like crystallites via reducing the contact surface until to the moment of spheroidization and attainment of isolation that occurred at Т = 1100 ° С.Residual sulfate ions slowed down the surface diffusion during heat treatment thus retaining quasy-spherical morphology and low aggregation degree of Y2O3 nanopowders.Sulfate-doped yttria nanopowders with medium particle size of 53 ± 13 nm possessed improved sinterability in comparison with undoped ones arising from finer particle size, narrower particle distribution and lower agglomeration degree.