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Updated: Jun 10, 2026
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Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
Biphasic Pd-Au alloy catalyst for low-temperature CO oxidation
1State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, People's Republic of China.
Journal of the American Chemical Society
|July 29, 2010
Summary
Palladium-gold nanoalloy catalysts show optimal low-temperature CO oxidation activity and stability. Biphasic separation into Pd-rich and Au-rich components enhances durability for catalytic applications.
Area of Science:
- Materials Science
- Catalysis
- Nanotechnology
Background:
- Low-temperature carbon monoxide (CO) oxidation is crucial for various catalytic applications.
- Palladium (Pd) and gold (Au) are key metals in catalysis, but their alloys' performance varies.
- Understanding nanoalloy structure-activity relationships is essential for catalyst design.
Purpose of the Study:
- To investigate the low-temperature CO oxidation performance of palladium-gold (Pd-Au) nanoalloy catalysts supported on silica fume.
- To correlate catalyst composition, structure, and surface properties with catalytic activity and stability.
- To explore the potential of biphasic Pd-Au nanoalloys as durable alternatives in catalysis.
Main Methods:
- Synthesis of a compositional series of Pd-Au nanoalloys on silica fume.
- Characterization using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron microscopy (HRTEM).
- In situ Fourier transform infrared (FTIR) spectroscopy during CO oxidation to study surface species.
Main Results:
- Pd-Au nanoalloys exhibited biphasic separation into Pd-rich and Au-rich components, except for pure metals.
- Optimal activity and stability at 300 K were observed for a Pd(4)Au(1) composition, a mixture of Pd-rich and Au-rich phases.
- Surface analysis revealed gold enrichment on Pd-rich alloys, and in situ FTIR indicated obscured Pd sites with increasing Au content.
Conclusions:
- Biphasic Pd-Au nanoalloys demonstrate superior performance and stability for low-temperature CO oxidation compared to pure Au catalysts.
- The observed gold enrichment and surface site blocking in Pd-rich alloys contribute to enhanced durability.
- Gold-containing biphasic Pd nanoalloys offer promising, highly durable alternatives for diverse catalytic reactions.
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