A Pt/Ce0.6Zr0.4O2 catalyst was synthesized by impregnating a Ce0.6Zr0.4O2 support with Pt(NO3)2 solu-tion. This material exhibits higher catalytic activity than Pt/Al2O3 for soot oxidation under loose contact conditions in both NO + O2 and O2 atmospheres. The results show that the pronounced ac-tivity of this catalyst is attributed to a synergistic effect arising from the combination of Pt and Ce0.6Zr0.4O2 solid solution, leading to a remarkable increase in the availability of active oxygen at temperatures as low as 450 °C. The NO↔NO2 recycling efficiency is improved over Pt/Ce0.6Zr0.4O2 catalyst, enhancing the ability of the NO2-soot reaction to generate surface oxygenated complexes (SOCs) on the soot. More importantly, the catalytic oxidation of these SOCs can be accelerated with the participation of active oxygen from the CeO2-ZrO2 solid solution. As a result, during soot oxida-tion under NO + O2, the light-off temperature of the Pt/Ce0.6Zr0.4O2 catalyst is lowered by 34 °C than that of Pt/Al2O3 catalyst.%通过在Ce0.6Zr0.4O2载体上浸渍Pt(NO3)2制得Pt/Ce0.6Zr0.4O2催化剂，该催化剂在松散接触条件下，于NO + O2或O2气氛中均表现出比Pt/Al2O3更好的碳烟氧化性能.进一步研究表明， Pt/Ce0.6Zr0.4O2催化剂中的Pt 与Ce0.6Zr0.4O2存在相互作用，使得催化剂在一定温度范围内对活性氧的利用率大为提高，从而促进了气氛中NO ↔ NO2的循环，乃至碳烟与NO2的反应和碳烟表面含氧中间物种的生成；更重要的是，这部分活性氧本身可加速含氧中间物种的分解.因此，在NO + O2的气氛中， Pt/Ce0.6Zr0.4O2催化剂的碳烟起燃温度比Pt/Al2O3降低了34°C.
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