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Laser illumination-induced dramatic catalytic activity change on Au nanospheres
Zhongju Ye1, Lin Wei2, Lehui Xiao1
1State Key Laboratory of Medicinal Chemical Biology , Tianjin Key Laboratory of Biosensing and Molecular Recognition , College of Chemistry , Nankai University , Tianjin , 300071 , China . Email: lehuixiao@nankai.edu.cn ; http://www.xiaolhlab.cn.
Chemical Science
|July 12, 2019
Summary
Single gold nanoparticles (GNPs) were reshaped into gold nanorods (GNRs) to study morphology-dependent catalysis. Spherical GNPs showed higher catalytic efficiency than GNRs due to surface structure differences.
Area of Science:
- Nanotechnology
- Materials Science
- Catalysis
Background:
- Understanding morphology-dependent catalytic kinetics of single nanoparticles is crucial for developing efficient nano-catalysts.
- Detailed knowledge of catalytic properties after nanoparticle shape transitions is currently lacking.
Purpose of the Study:
- To disclose the distinct catalytic properties of a single gold nanoparticle (GNP) after symmetry breaking at the single-particle level.
- To investigate the impact of shape transition from spherical GNP to gold nanorod (GNR) on catalytic efficiency.
Main Methods:
- Spherical gold nanoparticles (GNPs) were elongated into gold nanorods (GNRs) using a focused Gaussian laser beam via photothermal effect.
- Catalytic efficiency was studied using the amplex red to resorufin oxidation reaction as a model.
- Transmission electron microscopy (TEM) was used for surface structure characterization.
Main Results:
- A noticeable variation in catalytic efficiency was observed after shape modulation at the single-particle level.
- Spherical GNPs exhibited significantly higher catalytic efficiency compared to GNRs.
- TEM confirmed heterogeneous lattice structure on GNP surfaces, contributing to higher efficiency.
Conclusions:
- The study reveals morphology-dependent catalytic properties of gold nanoparticles after shape transitions.
- Surface atomic rearrangement during shape modulation leads to changes in catalytic activity.
- Dynamic activity fluctuations indicate spontaneous surface restructuring, relevant for heterogeneous catalyst development.
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