Sintering of nanopowder based on an ordered phase with a perovskite-type LaLuO₃:Yb³⁺structure

The present work developed a methodology for synthesising single-phase nanopowder based on an ordered phase with LaLuO3 perovskite type structure. The LaLu O_3 : Yb³⁺ nanopowder, doped with 2mol% Yb³⁺ , was synthesised by wet-chemical method from precursor nitrate solution and thermal treated to form pure perovskite phase. The synthesised nanopowder was comprehensively studied using IR spectroscopy, X-ray diffraction, scanning electron microscopy and adsorption-structural methods. The results of the X-ray diffraction analysis indicate that the synthesised powder is single-phase, with all the formed diffraction peaks corresponding to the ordered structure of the LaLu O_3 perovskite type. The unit cell parameters of the LaLu O_3 : Yb³⁺ (2mol%) phase are: a = 0.6023 nm, b = 0.8385 nm, c = 0.5822 nm and V = 0.294 nm3 whereas the average crystallite size is 51.2 nm. The nanopowder was consolidated using the spark plasma sintering (SPS) technique at 1380°C and 50MPa with dwell of 15min, resulting in a fully dense ceramic material of 8.16 g/ cm³ (i.e. 99.54% theoretical density).