To achieve high fuel efficiency and low emission in automobiles, it is necessary to develop highly active diesel oxidation catalysts (DOCs). Pd/CeO₂ catalysts have been widely used as active catalysts for CO and C₃H₆ oxidation reactions. Additionally, Ag has been reported to enhance the oxygen storage capacity (OSC) of CeO₂, which contributes to the oxidation ability of Pd/CeO₂. In this study, Pd/Ag-CeO₂ catalysts were used for CO and C₃H₆ oxidation reactions. When CeO₂ was doped with appropriate amounts of Ag, reducibility and CO desorption rate were increased, which confirmed the high OSCs of Ag-doped catalysts. However, Ag particles were formed and the Ce³⁺/Ce⁴⁺ ratio decreased when CeO₂ was doped with excess amounts of Ag. In addition, reduced Pd (Pd⁰), which is an active species for C₃H₆ oxidation, was formed and maintained even under oxidative reaction conditions. Since the removal of C₃H₆ is important for the oxidation of CO and C₃H₆, the catalyst with the highest Pd⁰ fraction (Pd/0.1Ag-CeO₂ and Pd/0.3Ag-CeO₂) presented improved catalytic activity. Consequently, the optimal amount of Ag enhanced the OSC of Pd/Ag-CeO₂ catalysts and formed active Pd⁰ species under oxidative conditions, which resulted in the excellent catalytic activity of Pd/Ag-CeO₂ for the CO and C₃H₆ oxidation reaction.

为了实现汽车的高燃料效率和低排放，有必要开发高活性柴油氧化催化剂（DOC）。Pd / CeO ₂催化剂已被广泛用作CO和C ₃ H ₆氧化反应的活性催化剂。另外，据报道，Ag增强了CeO _2的储氧能力（OSC），这有助于Pd / CeO ₂的氧化能力。在这项研究中，Pd / Ag-CeO ₂催化剂用于CO和C ₃ H _6的氧化反应。当CeO ₂用适量的Ag掺杂Ag，可还原性和CO解吸速率提高，这证实了Ag掺杂催化剂的高OSC。然而，当CeO ₂掺杂过量的Ag时，形成了Ag颗粒并且Ce ³⁺ / Ce ⁴⁺比率降低。此外，即使在氧化反应条件下，也形成并保持了还原的Pd（Pd ⁰），其是C ₃ H ₆氧化的活性物种。由于去除C ₃ H ₆对于CO和C ₃ H ₆的氧化非常重要，因此具有最高Pd ⁰分数（Pd / 0.1Ag-CeO _2）的催化剂Pd / 0.3Ag-CeO ₂）的催化活性提高。因此，最适量的Ag可增强Pd / Ag-CeO ₂催化剂的OSC，并在氧化条件下形成活性Pd ⁰物种，从而导致Pd / Ag-CeO ₂对CO和C ₃ H ₆的优异催化活性。氧化反应。