Synthesis of nanocrystalline Sc 2 O 3 powder and fabrication of transparent Sc 2 O 3 ceramics

Abstract

Synthesis of nanocrystalline Sc₂O₃ powder via a homogeneous precipitation method and fabrication of transparent Sc₂O₃ ceramics with vacuum sintering has been investigated here. Hydrated basic carbonate–sulphate precursor was synthesised from scandium sulphate and urea solution. Phase transformation processes of the precursor upon calcination were analysed. The resultant Sc₂O₃ powder is highly pure, ultrafine (50 nm), well dispersed, narrow particle size distribution, spherical and highly sinterable. Transparent Sc₂O₃ ceramics were fabricated using the excellent powder. The final pH value of the solution has a significant influence on sintering properties of the powder, which directly affects the transmittance of the ceramics. The sulphate system also plays an important role in powder properties.