Liu Ziwen, Zhang Guizhen, Niu Lijuan, Sun Zaicheng, Li Zhenguo, He Hong
Beijing Key Laboratory for Green Catalysis and Separation, College of Materials Science & Engineering, Beijing University of Technology, Beijing 100124, China.
Institute of Engineering Technology, Sinopec Catalyst Co., Ltd., Beijing 101111, China.
Nanomaterials (Basel). 2025 Jan 27;15(3):197. doi: 10.3390/nano15030197.
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/AlO-xCeO) that are selectively decorated by CeO, which form core-shell-like structures and generate more Pd-CeO interfacial sites, so that the three-way catalytic activity of Pd/AlO-xCeO catalysts is obviously significantly enhanced due to more adsorption oxygen at the interface of Pd-CeO and good low-temperature reducibility. At the moment, the Pd/AlO-xCeO catalysts exhibit excellent thermal stability after being calcined at 900 °C for 5 h, owing to the Pd species being highly redispersed on CeO and part of the Pd species being incorporated into the lattice of CeO. This is a major reason for the Pd/AlO-xCeO 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 CeO are responsible for the excellent catalytic performance and stability of Pd/AlO-xCeO catalysts in three-way reactions.
金属-氧化物界面在多相催化中起着重要作用。对金属-氧化物界面进行调控可有效提高贵金属催化剂的催化活性和热稳定性。在本工作中，采用聚乙烯醇保护还原法和L-精氨酸诱导法制备了由CeO选择性修饰的Pd催化剂（Pd/AlO-xCeO），其形成核壳状结构并产生更多的Pd-CeO界面位点，使得Pd/AlO-xCeO催化剂的三效催化活性因Pd-CeO界面处更多的吸附氧和良好的低温还原性而明显显著增强。此时，Pd/AlO-xCeO催化剂在900℃下煅烧5小时后表现出优异的热稳定性，这是由于Pd物种高度分散在CeO上且部分Pd物种掺入CeO晶格中。这是Pd/AlO-xCeO催化剂在高温老化后仍保持高催化活性的主要原因。得出结论，金属-氧化物界面以及Pd纳米颗粒与CeO之间的相互作用是Pd/AlO-xCeO催化剂在三效反应中具有优异催化性能和稳定性的原因。
