Influence of sulfate ions on properties of co-precipitated Y3Al5O12:Nd3+ nanopowders

A new precursor of yttrium aluminum garnet with an approximate composition of NH4AlY0.6(CO3)x(OH)y(SO4)z·nH2O has been synthesized via a reverse strike co-precipitation method with ammonium hydrogen carbonate as the precipitant and ammonium aluminum sulfate as the sulfate ions source. The evolution of phase, chemical composition and morphology of the precursor during calcination has been studied by means of XRD, XPS, DTA–TG, BET methods and FT-IR spectroscopy. The loosely agglomerated powders with narrow size distribution, spherical shapes and diameter of 50–60 nm have been obtained by calcination of the sulfate-containing precursor at 1100 °C for 2 h. The doping by sulfate ions enhances densification of Y3Al5O12:Nd3+ nanopowders compared to undoped ones. This leads to improved microstructure and optical transmittance of vacuum sintered ceramics prepared from sulfate-doped nanopowders.

Research highlights▶ A new sulfate-containing precursor of YAG has been synthesized by co-precipitation method. ▶ Sulfate ions doped YAG nanopowders have better dispersion compared to undoped ones. ▶ Sulfate ions reduce crystal anisotropy among crystal planes of YAG:Nd3+ during calcinations. ▶ The doping by sulfate ions enhances densification of Y3Al5O12:Nd3+ nanopowders.