| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1619276 | Journal of Alloys and Compounds | 2010 | 7 Pages |
Ce0.67Zr0.33O2 (CZ) mixed oxide was prepared by coprecipitation and effect of the synthesis conditions on CZ properties were investigated in this work, as well as the catalytic performance of Pd-only three-way catalyst (TWC) supported on the prepared CZ. With the increase of aging temperature during precipitation, the crystallite size of CZ increases significantly, while the oxygen storage capacity complete (OSCC) drops and no notable effect on porosity of CZ is observed. The porosity is mainly determined by drying temperature and pH value during precipitation. Prepared under optimized conditions (precipitation at the pH of 9.5, aging at 25 °C and then drying under supercritical condition in alcohol), the CZ samples exhibit good properties. This preparation procedure leads to CZ with proper pore size distribution, larger average pore size (20.42 nm), higher pore volume (0.69 cm3/g) and enhanced OSCC value (383.0 μmol/g). Furthermore, the Pd-only TWC supported on the CZ synthesized under the optimized conditions exhibits satisfactory catalytic activity and very low reduction temperature (53 °C).
Research highlights▶ In this paper, influence of synthesis condition on properties of Ce0.67Zr0.33O2 (CZ) mixed oxides was firstly studied in detail and coprecipitation was taken as the standard method. ▶ With the increase of aging temperature during precipitation, the crystallite size of CZ increases significantly, while the oxygen storage capacity complete (OSCC) drops and no notable effect on porosity of CZ is observed. Drying temperature has a significant influence on the porosity rather than on the structural properties of CZ. Moreover, the textural and structural properties of CZ are affected by the pH value during precipitation. ▶ The catalytic activity of Pd-only three-way catalyst (TWC) is related to the properties of CZ mixed oxides and the reducibility of PdO species. The best synthesis condition of CZ was obtained and the Pd-only TWC supported on this support exhibits the best catalytic activity.
