Tailoring Metal-Oxide Interfaces via Selectively CeO2-Decorated Pd Nanocatalysts with Enhanced Catalytic Performance

Metal-oxide interfaces play a prominent role in heterogeneous catalysis. Tailoring the metal-oxide interfaces effectively enhance the catalytic activities and thermal stability of noble metal catalysts. In this work, polyvinyl alcohol-protected reduction and L-arginine induction methods are adopted to prepare Pd catalysts (Pd/Al2O3-xCeO2) that are selectively decorated by CeO2, which form core-shell-like structures and generate more Pd-CeO2 interfacial sites, so that the three-way catalytic activity of Pd/Al2O3-xCeO2 catalysts is obviously significantly enhanced due to more adsorption oxygen at the interface of Pd-CeO2 and good low-temperature reducibility. At the moment, the Pd/Al2O3-xCeO2 catalysts exhibit excellent thermal stability after being calcined at 900 degrees C for 5 h, owing to the Pd species being highly redispersed on CeO2 and part of the Pd species being incorporated into the lattice of CeO2. This is a major reason for the Pd/Al2O3-xCeO2 catalysts to maintain high catalytic activity after aging at high temperatures. It is concluded that the metal-oxide interfaces and the interaction between Pd NPs and CeO2 are responsible for the excellent catalytic performance and stability of Pd/Al2O3-xCeO2 catalysts in three-way reactions.