Structural Transformation and Low-Pressure Catalysis for Ethyl Acetate Hydrogenation of Rh/One-Atomic-Layer GeO2/SiO2

We prepared a new Rh/one-atomic-layer GeO 2 /SiO 2 catalyst by supporting Rh 6 (CO) 16 precursor on the one-atomic-layer GeO 2 /SiO 2 . The obtained catalyst was active for conversion of ethyl acetate to ethanol by H 2 reduction under mild reaction conditions. Three different structures and chemical states of Rh species on the one-atomic-layer GeO 2 /SiO 2, characterized by EXAFS, TPD, TEM, and FT-IR, were formed depending on the prereduction temperature, Rh carbonyl cluster, Rh metal, and RhGe alloy. The Rh atoms in the metallic state were most active for the ethanol formation. The one-atomic-layer GeO 2 was much more effective as support for the Rh metallic particles than three-dimensional GeO 2 particles dispersed on SiO 2 . Rh/bulk-GeO 2 and Rh/SiO 2 were inactive for this reaction. Ethyl acetate dissociatively adsorbed on the one-atomic-layer GeO 2, while hydrogen adsorbed on the Rh metallic particles. The present study exemplifies the advantageous applications of an inorganic oxide monolayer to preparation of supported metal catalysts.