Solvent effects on formation of Cr-doped Ce0.2Zr0.8O2 synthesized with cinnamic acid and their catalysis in oxidation of NO

Cr-doped Ce0.2Zr0.8O2 was synthesized with cinnamic acid as ligand, and four different solvents (H2O, ethanol, ethylene glycol and isopropanol) were added into the precursor solution to contrast with each other. These catalysts were investigated in detail by means of X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area analysis, High resolution transmission electron microscope (HR-TEM), Ultra violet-visible diffuse reflectance spectroscopy (UV-vis DRS), X-ray photoelectron spectroscopy (XPS) and NO(O-2) Temperature-programmed desorption (NO(O-2)-TPD). The results indicated that the preparation process adopted with one-step method simplified the experimental procedure, decreased the size of particle and increased the specific surface area of the catalysts. Moreover, the solvent with appropriate polarity could decrease the band gap of the catalysts and benefit for more generation of Ce3+ and Cr6+ on the surface of the catalyst, which was beneficial for the adsorption of NO and O-2. All catalysts showed broad activity temperature window and the catalyst adopted with ethylene glycol as solvent exhibited the highest NO conversion, which achieved 66.32% at 350 degrees C. (C) 2014 Elsevier B.V. All rights reserved.