Ce_xZr_(1-x)O₂ (x = 0.27, 0.50 and 0.73) mixed oxides were prepared by co-precipitation method and then aged at 700–1000 °C. The reducibility of the aged catalysts was investigated by H₂-TPR. It was found that the changes in reduction properties are related to the Ce/Zr ratio and Ce_0.27Zr_0.73O₂ shows an increased H₂ consumption with aging temperature increasing, even 1000 °C-aged samples show an increased reduction ability. Raman, XPS and HRTEM reveal that the promotion on reduction property of the aged samples should be ascribed to the increase of surface oxygen species, surface Ce/Zr ratio, O-vacancies and (110) and (100) planes. However, this promotion can not obviously improve soot oxidation activity. XRD, BET and O₂-TPD results reveal that textural, structural and oxygen desorption properties are crucial to soot oxidation activity. The poor contact between soot and active sites would be an important factor that leads to a contradiction between H₂-TPR and soot-O₂ reaction activity.

通过共沉淀法制备了Ce _x Zr _（1-x） O ₂（x = 0.27、0.50和0.73）混合氧化物，然后在700–1000°C时效。通过H ₂ -TPR研究了老化催化剂的还原性。发现还原性能的变化与Ce / Zr比有关，并且Ce _0.27 Zr _0.73 O ₂显示出增加的H _2。随着时效温度的升高，即使是1000°C时效的样品，其还原能力也会提高。Raman，XPS和HRTEM表明，老化样品还原性能的提高应归因于表面氧种类，表面Ce / Zr比，O空位以及（110）和（100）平面的增加。但是，这种促进不能明显改善烟灰的氧化活性。XRD，BET和O ₂ -TPD结果表明，结构，结构和氧解吸性质对烟ot氧化活性至关重要。烟灰与活性位点之间的不良接触将是导致H ₂ -TPR与烟灰-O ₂反应活性之间矛盾的重要因素。