Synthesis of nano-hollow-shaped rare earth oxides by glycothermal treatment of rare earth acetates and subsequent calcination

The reaction of yttrium acetate hydrate in 1,2-propanediol (1,2-PG) at 300 °C yielded the products containing the acetate groups and the glycol moieties. The products decomposed into Y2O3 below 400 °C, and the thus-obtained Y2O3 samples had quite large surface areas (>200 m2/g) and were comprised of crystalline nano-hollow spheres with the outer diameter of 7–18 nm and the inner diameter of 2–8 nm. Dy2O3, Er2O3 and Yb2O3 composed of nano-hollow spheres were also obtained by the glycothermal treatment and subsequent calcination.