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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
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Alkyl and Aromatic Amines as Digestive Ripening/Size Focusing Agents for Gold Nanoparticles
Yijun Sun1, Deepa Jose2, Christopher Sorensen3
1Department of Chemistry, Kansas State University, Manhattan, KS 66506, USA. julia.yj.sun@gmail.com.
Nanomaterials (Basel, Switzerland)
|March 29, 2017
Summary
Alkyl amines and thiols focus gold nanoparticle size via thermodynamic control. Amines utilize a distinct digestive ripening mechanism, differing from thiol oxidation, impacting final particle size.
Area of Science:
- Nanotechnology
- Materials Science
- Physical Chemistry
Background:
- Long chain alkyl thiols and amines act as size-focusing agents for gold nanoparticles.
- Both processes are governed by thermodynamic control.
- Thiols oxidize gold surface atoms, unlike amines, suggesting different mechanisms.
Purpose of the Study:
- To investigate the mechanism of size focusing by alkyl amines.
- To compare the efficiency of various alkyl amines, including aromatic and reactive types.
- To analyze the impact of different nanoparticle preparation methods on size focusing.
Main Methods:
- Investigated varying alkyl amine chain lengths and structures (aniline, 2-phenylethyl amine).
- Employed two gold nanoparticle synthesis methods: gold ion reduction/inverse micelle and metal vaporization (Solvated Metal Atom Dispersion-SMAD).
- Analyzed the thermodynamic control and digestive ripening mechanisms.
Main Results:
- Alkyl amines facilitate size focusing through a distinct mechanism compared to thiols.
- The efficiency of size focusing varies with amine structure and chain length.
- Different preparation methods (inverse micelle vs. SMAD) yield distinct gold nanoparticle size distributions.
Conclusions:
- Alkyl amines offer an alternative pathway for gold nanoparticle size focusing via digestive ripening.
- Understanding these mechanisms allows for tailored control over nanoparticle size.
- The choice of synthesis method significantly influences the outcome of size focusing agents.
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