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Updated: Jul 3, 2026
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Preparation of Silver-Palladium Alloyed Nanoparticles for Plasmonic Catalysis under Visible-Light Illumination
Published on: August 18, 2020
Plasmonic Re-Excitation Enables Superoxide-Mediated Ethane Conversion to Acetic Acid under Visible Light
Lei Luo1, Donghui Li1, Zongxu Wu1
1State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, P. R. China.
Journal of the American Chemical Society
|July 2, 2026
Summary
Plasmonic gold nanoparticles enable tungsten oxide to selectively upgrade ethane using visible light. This method controls superoxide generation for efficient acetic acid synthesis, overcoming previous selectivity challenges in photocatalysis.
Area of Science:
- Materials Science
- Photocatalysis
- Green Chemistry
Background:
- Photocatalytic alkane upgrading offers a sustainable route for chemical synthesis.
- Poor selectivity due to unselective reactive oxygen species (ROS) limits current methods.
- Controlling ROS, specifically favoring superoxide (·O2-) over hydroxyl radicals (·OH), is crucial for targeted reactions.
Purpose of the Study:
- To develop a photocatalytic system for selective alkane upgrading.
- To investigate the role of plasmonic nanoparticles in controlling ROS generation.
- To achieve selective oxidation of ethane to acetic acid using visible light.
Main Methods:
- Coupling tungsten oxide (WO3) semiconductor with plasmonic gold (Au) nanoparticles.
- Utilizing visible light irradiation (λ > 420 nm) to drive the photocatalytic reaction.
- Analyzing the generated intermediates and products, including superoxide and acetic acid.
Main Results:
- Au-WO3 composite facilitates photoelectron re-excitation, favoring the superoxide pathway.
- Enhanced charge separation and sustained ·O2- generation were observed.
- Achieved benchmark ethane oxidation with >80% selectivity to acetic acid (CH3COOH), reaching 100 mmol·L-1.
Conclusions:
- Plasmonic re-excitation by Au nanoparticles enables controlled superoxide generation.
- This strategy overcomes the limitations of unselective ROS in photocatalysis.
- Establishes a general paradigm for selective oxygenate synthesis via visible-light photocatalysis.
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