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Effect of experimental conditions on size control of Au nanoparticles synthesized by atmospheric microplasma electrochemistry.

Huang X, Li Y, Zhong X - Nanoscale Res Lett (2014)

Bottom Line: The Au NPs often with small size were synthesized as a result of stirring.The production rate, the electrostatic repulsion, and the residence time of the Au NPs at the interfacial region play an important role in the growth of Au NPs.The results shed light upon the roadmap to control the size and particle size distribution (PSD) of Au NPs synthesized by atmospheric microplasma electrochemistry.

View Article: PubMed Central - HTML - PubMed

Affiliation: State Key Laboratory of Advanced Optical Communication Systems and Networks, Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.

ABSTRACT
Atmospheric microplasma electrochemistry was utilized to synthesize Au nanoparticles (NPs). The synthesized Au NPs were investigated as a function of reduction current, solution temperature, and stirring (or not) by using ultraviolet-visible (UV-Vis) absorbance and transmission electron microscopy (TEM). It was illustrated that high current promoted the growth of Au NPs with small size, and more Au NPs with large size were synthesized as a rise of temperature. The Au NPs often with small size were synthesized as a result of stirring. The production rate, the electrostatic repulsion, and the residence time of the Au NPs at the interfacial region play an important role in the growth of Au NPs. The results shed light upon the roadmap to control the size and particle size distribution (PSD) of Au NPs synthesized by atmospheric microplasma electrochemistry.

No MeSH data available.


UV–vis absorbance spectroscopy (a), TEM images (b, b’), and PSD (c, c’) of Au NPs. Synthesized at a temperature of 70°C, using 15 mA of current with and without stirring condition.
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Figure 4: UV–vis absorbance spectroscopy (a), TEM images (b, b’), and PSD (c, c’) of Au NPs. Synthesized at a temperature of 70°C, using 15 mA of current with and without stirring condition.

Mentions: As the current increases, more electrons are injected from plasma into the solution per unit time; as a result, more Au NPs are produced per unit time, i.e. the production rate of Au NPs increases. Since not all the electrons injected by the plasma are involved in Au3+ reduction [32], the remaining electrons are involved in the charge-transfer process such as charging the produced Au NPs at the interfacial region [30]. Obviously, the higher current leads to the higher production rate of Au NPs and as a result, the more and more Au NPs are being charged. The charged Au NPs repel each other, impede the agglomeration and the growth of the Au NPs, and lead to the production of the Au NPs with smaller size.Figure 4a presents the UV-Vis absorbance spectroscopies of the Au colloids produced at the condition with and without stirring. Both of experiments were carried out at the current of 15 mA and the temperature of 70°C. The stirring reduces the UV-Vis absorbance at the longer wavelength which specifies the decrease of Au NPs with large size; nevertheless, clear blue shift of the absorption peak is not identified. Figure 4b,b’,c,c’ shows TEM images and PSD of Au colloids produced at the condition with and without stirring, respectively. Both TEM images and PSD of Au NPs illustrate that the NPs synthesized under the condition with stirring are relatively small and uniform.


Effect of experimental conditions on size control of Au nanoparticles synthesized by atmospheric microplasma electrochemistry.

Huang X, Li Y, Zhong X - Nanoscale Res Lett (2014)

UV–vis absorbance spectroscopy (a), TEM images (b, b’), and PSD (c, c’) of Au NPs. Synthesized at a temperature of 70°C, using 15 mA of current with and without stirring condition.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4214825&req=5

Figure 4: UV–vis absorbance spectroscopy (a), TEM images (b, b’), and PSD (c, c’) of Au NPs. Synthesized at a temperature of 70°C, using 15 mA of current with and without stirring condition.
Mentions: As the current increases, more electrons are injected from plasma into the solution per unit time; as a result, more Au NPs are produced per unit time, i.e. the production rate of Au NPs increases. Since not all the electrons injected by the plasma are involved in Au3+ reduction [32], the remaining electrons are involved in the charge-transfer process such as charging the produced Au NPs at the interfacial region [30]. Obviously, the higher current leads to the higher production rate of Au NPs and as a result, the more and more Au NPs are being charged. The charged Au NPs repel each other, impede the agglomeration and the growth of the Au NPs, and lead to the production of the Au NPs with smaller size.Figure 4a presents the UV-Vis absorbance spectroscopies of the Au colloids produced at the condition with and without stirring. Both of experiments were carried out at the current of 15 mA and the temperature of 70°C. The stirring reduces the UV-Vis absorbance at the longer wavelength which specifies the decrease of Au NPs with large size; nevertheless, clear blue shift of the absorption peak is not identified. Figure 4b,b’,c,c’ shows TEM images and PSD of Au colloids produced at the condition with and without stirring, respectively. Both TEM images and PSD of Au NPs illustrate that the NPs synthesized under the condition with stirring are relatively small and uniform.

Bottom Line: The Au NPs often with small size were synthesized as a result of stirring.The production rate, the electrostatic repulsion, and the residence time of the Au NPs at the interfacial region play an important role in the growth of Au NPs.The results shed light upon the roadmap to control the size and particle size distribution (PSD) of Au NPs synthesized by atmospheric microplasma electrochemistry.

View Article: PubMed Central - HTML - PubMed

Affiliation: State Key Laboratory of Advanced Optical Communication Systems and Networks, Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.

ABSTRACT
Atmospheric microplasma electrochemistry was utilized to synthesize Au nanoparticles (NPs). The synthesized Au NPs were investigated as a function of reduction current, solution temperature, and stirring (or not) by using ultraviolet-visible (UV-Vis) absorbance and transmission electron microscopy (TEM). It was illustrated that high current promoted the growth of Au NPs with small size, and more Au NPs with large size were synthesized as a rise of temperature. The Au NPs often with small size were synthesized as a result of stirring. The production rate, the electrostatic repulsion, and the residence time of the Au NPs at the interfacial region play an important role in the growth of Au NPs. The results shed light upon the roadmap to control the size and particle size distribution (PSD) of Au NPs synthesized by atmospheric microplasma electrochemistry.

No MeSH data available.