Designing ultrastable Pt/CeO2-Al2O3 nanosheet catalysts for three-way catalysts applications
Designing ultrastable Pt/CeO2-Al2O3 nanosheet catalysts for three-way catalysts applications
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DOI：
10.1016/j.cej.2023.147086
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发表时间：
2023-11
影响因子：
15.1
通讯作者：
Junjie Chen;Chih-Han Liu;H. Pham;T. Toops;A. Datye;Eleni A. Kyriakidou
中科院分区：
文献类型：
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作者：
Junjie Chen;Chih-Han Liu;H. Pham;T. Toops;A. Datye;Eleni A. Kyriakidou
设计具有改进的低温活性/稳定性的无Rh，特别是仅Pt的三效催化剂是非常期望的。在此，我们证明，超稳定的Pt/CeO 2-Al 2 O3纳米片催化剂可以获得基于Sabatier原则的金属-载体相互作用。通过CeO 2“纳米岛”（对Pt的强粘附）调节富五位γ-Al 2 O3纳米片（AlNS，对Pt的弱粘附）的表面覆盖度，可以合成Pt/60 wt.% CeO 2-AlNS催化剂与传统Pt/CeO 2和Pt/Al 2 O3催化剂相比，CO、烃和NO的起燃温度低100-200 °C，并且与最先进的Rh基催化剂具有相似的性能。在AlNS表面包覆CeO 2可以抑制CeO 2在苛刻的氧化还原水热老化过程中的烧结，这与CeO 2“纳米岛”与富五位γ-Al 2 O3纳米片之间的强相互作用有关。此外，Pt/CeO 2-AlNS催化剂的改进的活性/稳定性可归因于分别调节Pt从CeO 2“纳米岛”的脱离和迁移，这保持Pt作为CeO 2上的纳米团簇，这是三效催化剂应用中最具活性的物种。
Designing Rh-free, especially Pt-only, three-way catalysts with improved low-temperature activity/stability is highly desirable. Herein, we demonstrate that ultrastable Pt/CeO2-Al2O3nanosheet catalysts can be obtained based on a Sabatier principle of metal-support interaction. Tuning the surface coverage of penta-site rich γ-Al2O3nanosheets (AlNS, weak adhesion to Pt) by CeO2“nano-islands” (strong adhesion to Pt) can lead to the synthesis of Pt/60 wt.%CeO2-AlNS that have lower light-off temperatures for CO, hydrocarbons, and NO compared to conventional Pt/CeO2and Pt/Al2O3catalysts by 100–200 °C and a similar performance with the state-of-the-art Rh-based catalyst. Incorporating CeO2on the surface of AlNS can retard the sintering of CeO2during harsh redox hydrothermal aging, associate with the strong interaction between CeO2“nano-island” and penta-site rich γ-Al2O3nanosheets. Moreover, the improved activity/stability of Pt/CeO2-AlNS catalysts can be attributed to tuning of the Pt detachment and migration from and back to the CeO2“nano-islands”, respectively, that keeps Pt as nanoclusters on CeO2, the most active species for three-way catalyst applications.