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Updated: Jan 14, 2026
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Tuning the Acidity of Pt/ CNTs Catalysts for Hydrodeoxygenation of Diphenyl Ether
Published on: August 17, 2019
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Temperature-driven mechanistic transition in propylene oxidation over Pt/CeO2 ensemble catalysts
Zihao Li1,2, Xingyan Chen1, Yao Lv3
1State Key Laboratory of Green Papermaking and Resource Recycling, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China.
Nature Communications
|October 16, 2025
Summary
Hydrogen-activated platinum-cerium oxide (Pt/CeO2) catalysts use metallic platinum ensembles for propylene oxidation. A 170°C threshold reveals dynamic changes in reaction mechanisms and oxygen activation.
Area of Science:
- Heterogeneous catalysis
- Surface chemistry
- Environmental catalysis
Background:
- Platinum-cerium oxide (Pt/CeO2) catalysts are crucial for vehicle exhaust treatment.
- Understanding active sites and temperature-dependent interface evolution in Pt/CeO2 for propylene (C3H6) oxidation is challenging.
Purpose of the Study:
- To identify the intrinsic active sites of H2-activated Pt/CeO2 ensemble catalysts.
- To elucidate the dynamic evolution of the metal-support interface during propylene oxidation at varying temperatures.
Main Methods:
- Operando characterization techniques
- Kinetic studies
- Theoretical analysis (DFT)
Main Results:
- H2-activated Pt/CeO2 catalysts exhibit metallic Pt ensembles as active sites, reducing the 50% conversion temperature by 120°C.
- A threshold temperature of ~170°C was identified for dynamic changes in reaction mechanisms.
- Oxygen-facilitated dehydrogenation of sp3 C-H bonds is the rate-determining step.
- Low-temperature mechanism involves Pt-only activation; high-temperature mechanism involves Pt-O-Ce interfaces.
Conclusions:
- Metallic Pt ensembles are the intrinsic active sites for propylene oxidation over H2-activated Pt/CeO2.
- Propylene oxidation exhibits distinct temperature regimes due to dynamic oxygen activation at the Pt-CeO2 interface.
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