Synthesis of Mesoporous Needle-Shaped Ytterbium Oxide Crystals by Solvothermal Treatment of Ytterbium Chloride
The reaction of rare-earth (RE; Y, Er, and Yb) chloride hydrates in 1,4-butanediol at 300°C for 2 h gave mixtures of RE(OH)2Cl and RE2O3·xH2O, and the products were composed of irregularly shaped particles. A prolonged reaction (10 h) yielded a mixture of RE(OH)2Cl and RE2O3·xH2O for Er or Y, but phase-pure RE2O3·xH2O was obtained for Yb. The product for Yb comprised needle-shaped single crystals of Yb2O3·xH2O with a width of 0.2–0.6 m and a length of 5–15 m. The Yb2O3·xH2O phase decomposed to Yb2O3 at 350°–500°C, preserving the needle-shaped morphology; this was maintained even after calcination at 1100°C. Single crystals of Yb2O3 obtained by the calcination of Yb2O3·xH2O at 500°C had very small voids and the voids were enlarged to 35 Å in diameter by calcination at 800°C.
No Supplementary Data
No Article Media
Document Type: Research Article
Affiliations: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto 615-8510, Japan
Publication date: April 1, 2007