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A Simple Method for the Size Controlled Synthesis of Stable Oligomeric Clusters of Gold Nanoparticles under Ambient Conditions
Published on: February 5, 2016
Magic numbers of gold clusters stabilized by PVP
Hironori Tsunoyama1, Tatsuya Tsukuda
1Catalysis Research Center, Hokkaido University, Nishi 10, Kita 21, Sapporo 001-0021, Japan.
Journal of the American Chemical Society
|December 9, 2009
Summary
Researchers used MALDI mass analysis to study gold (Au) clusters stabilized by poly(vinyl-pyrrolidone) (PVP). They identified specific gold cluster sizes, or "magic numbers," revealing deviations from theoretical models due to PVP interaction.
Area of Science:
- Physical Chemistry
- Materials Science
- Nanotechnology
Background:
- Gold clusters exhibit unique properties based on their size.
- The electronic shell model predicts specific stable cluster sizes (magic numbers).
- Poly(vinyl-pyrrolidone) (PVP) is commonly used to stabilize nanoparticles.
Purpose of the Study:
- To investigate the magic numbers of gold clusters stabilized by PVP.
- To compare the observed magic numbers with those of free gold clusters.
- To understand the influence of PVP on gold cluster stability and structure.
Main Methods:
- Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry was employed for precise mass analysis.
- The study focused on gold (Au) clusters.
- Poly(vinyl-pyrrolidone) (PVP) was used as a stabilizing agent.
Main Results:
- A series of magic numbers for Au cluster size were identified: 35±1, 43±1, 58±1, 70±3, 107±4, 130±1, and 150±2.
- Magic numbers below approximately 70 Au atoms aligned with predictions for free clusters and the electronic shell model.
- Magic numbers above approximately 100 Au atoms significantly deviated from the electronic shell model predictions.
Conclusions:
- The interaction between gold clusters and PVP perturbs their electronic and/or geometric structures.
- This perturbation leads to the observed deviations in magic numbers for larger gold clusters.
- PVP plays a crucial role in modifying the intrinsic properties of gold nanoclusters.
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