Characterization and Catalytic Functionalities of Copper Oxide Catalysts Supported on Zirconia

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• 作者：Komandur V. R. Chary ; Guggilla Vidya Sagar ; Chakravarthula S. Srikanth ; Vattikonda Venkat Rao
• 刊名：Journal of Physical Chemistry B
• 出版年：2007
• 出版时间：January 25, 2007
• 年：2007
• 卷：111
• 期：3
• 页码：543 - 550
• 全文大小：137K
• 年卷期：v.111,no.3(January 25, 2007)
• ISSN：1520-5207

文摘

A series of zirconia supported copper oxide catalysts with varying copper loadings (1.2-19.1 wt %) wereprepared by impregnation method. The catalysts were characterized by X-ray diffraction, UV-visible diffusereflectance spectroscopy, X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR),and temperature-programmed desorption of CO₂. Copper dispersion and metal area were determined by N₂Odecomposition method. X-ray diffraction patterns indicate the presence of crystalline CuO phase beyond 2.7wt % of Cu on zirconia. UV-visible diffuse reflectance spectra suggest the presence of two types of copperspecies on the ZrO₂ support. XPS peaks intensity ratio of Cu 2p_3/2 and Zr 3d_5/2 was compared with Cu dispersioncalculated from N₂O decomposition. TPR patterns reveal the presence of highly dispersed copper oxide atlower temperatures and bulk CuO at higher temperatures. The basicity of the catalysts was found to increasewith Cu loading, and the activity of the catalysts was also found to increase with the increase in Cu loadingup to 2.7 wt % Cu loading. The catalytic properties were evaluated for the dehydrogenation of cyclohexanolto cyclohexanone and were related to surface properties of the copper species supported on zirconia.