Preparation and formation mechanism of mesoporous CuO-CeO2 mixed oxides with excellent catalytic performance for removal of VOCs

A simple route has been developed to synthesize mesoporous CuO-CeO2 mixed oxides. X-ray diffraction, N-2 adsorption and desorption isotherms, and high-resolution transmission electron microscopy have been used to characterize the obtained mesoporous CuOCeO2 mixed oxides. The results revealed that the as-prepared CuO-CeO2 mixed oxides possessed a high BET surface area and pores in the range of 1-10 nm after calcination at 600 degrees C for 4 h. In order to understand the formation mechanism of the mesoporous structure, the precursor before calcination was characterized by FTIR and TG-DSC. The results showed that the formation of the mesoporous structure with the high BET surface area was ascribed to the decomposition of ammonia nitrate. Further experimental investigations revealed that the amount of ammonia nitrate in the precursor greatly influenced the BET surface area and the pore size of the final product. Furthermore, the method could be extended to the synthesis of other mixed oxides with the mesoporous structures, such as ZrO2CeO2 and ZrO2-Y2O3. The as-prepared mesoporous CuO-CeO2 sample with the high surface area exhibited highly reducible features as compared to the sample with a low surface area. The mesoporous CuO-CeO2 powder showed excellent catalytic activity for the complete oxidation of benzene. (C) 2007 Elsevier Inc. All rights reserved.