Characterization of Sol-Gel Derived CuO@SiO2 Nano Catalysts towards Gas Phase Reactions

Document Type : Research Article


1 Islamic Azad University, Rasht Branch, Rasht, I.R. IRAN

2 Agricaltur & Medical & Industrial Research School, Nuclear Science and Technology Institute, P. O. Box: 31485- 498, Karaj a, I.R. IRAN

3 Yerevan State University, 1 Alex Manoukian St., Yerevan 375049, ARMENIA


One distinct concentration of copper ions was embedded into the silica matrix to xerogel form using copper source Cu(NO3)23H2O. The xerogel samples were prepared with using hydrolysis and condensation reactions of TetraEthyl Ortho-Silicate (TEOS) by the sol-gel method. In this investigation, new molar ratio of H2O/TEOS was determined to be 11.7. Also, the necessary amount of tri-hydrated copper nitrate was added to the solution in such a manner that the concentration of the copper oxide in final solution reach to 10 wt. %. The prepared samples were characterized by Thermal Gravimetric Analysis (TGA), Transmission Electron Microscopy (TEM), surface area measurement (using BET method) and Thermal Program Reduction (TPR) methods. Finally, catalytic behavior of nano-composites was studied towards carbon monoxide (CO), nitrogen monoxide (NO) oxidation and di-nitrogen oxide (N2O) decomposition reactions.The results were presented the systematic reactivity study of CO, NO oxidation and N2O decomposition on dispersed copper oxide nano-catalysts over silica supports, in order to determine the ability of these materials to convert carbon monoxide, nitrogen monoxide and di-nitrogen oxide  to harmless species by different reaction paths at different temperatures.


Main Subjects

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