Controllable synthesis of Sm2O3 crystallites with the assistance of templates by a hydrothermal–calcination process

Sm2O3 crystallites were controllably synthesized by the hydrothermal–calcination process with the assistance of different templates. The phase compositions, morphologies and optical properties of the as-prepared samples were characterized by X-ray diffraction, scanning electron microscope and ultraviolet–visible spectrophotometer. It is investigated that the influence of different templates on the structural and optical properties of Sm2O3 samples. Results showed that Sm2O3 crystallites with ribbon-like, granular and flake-like morphologies were obtained when NaNO3, trisodium citrate and polyvinyl-pyrrolidone (PVP) were used as template agents. These templates effectively controlled the microstructure and optical properties of the as-prepared samples. The monoclinic phase Sm2O3 crystallites with ribbon-like morphology were prepared by using NaNO3 as the template agent, which energy gap is only 4.827 eV.