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Ultrasonic-aided fabrication of gold nanofluids.

Chen HJ, Wen D - Nanoscale Res Lett (2011)

Bottom Line: The ultrasonication technique is found to be a very powerful tool in engineering the size and shape of GNPs.Subsequent property measurement shows that both particle size and particle shape play significant roles in determining the effective thermal conductivity.A large increase in effective thermal conductivity can be achieved (approximately 65%) for gold nanofluids using plate-shaped particles under low particle concentrations (i.e.764 μM/L).

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Engineering and Materials Science, Queen Mary University of London, London, UK. d.wen@qmul.ac.uk.

ABSTRACT
A novel ultrasonic-aided one-step method for the fabrication of gold nanofluids is proposed in this study. Both spherical- and plate-shaped gold nanoparticles (GNPs) in the size range of 10-300 nm are synthesized. Subsequent purification produces well-controlled nanofluids with known solid and liquid contents. The morphology and properties of the nanoparticle and nanofluids are characterized by transmission electron microscopy, scanning electron microscope, energy dispersive X-ray spectroscope, X-ray diffraction spectroscopy, and dynamic light scattering, as well as effective thermal conductivities. The ultrasonication technique is found to be a very powerful tool in engineering the size and shape of GNPs. Subsequent property measurement shows that both particle size and particle shape play significant roles in determining the effective thermal conductivity. A large increase in effective thermal conductivity can be achieved (approximately 65%) for gold nanofluids using plate-shaped particles under low particle concentrations (i.e.764 μM/L).

No MeSH data available.


Average size of gold nanoparticles in DI water measured by a Zetasizer (blue points show the size of GNPs sonicated for 0, 30, and 45 min, and red points present the size of GNPs using a mixed magnetic stirring and ultrasonication of total 30 min).
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Figure 3: Average size of gold nanoparticles in DI water measured by a Zetasizer (blue points show the size of GNPs sonicated for 0, 30, and 45 min, and red points present the size of GNPs using a mixed magnetic stirring and ultrasonication of total 30 min).

Mentions: With the application of ultrasonication during the synthesis (Group B samples), the particle size becomes smaller, being reduced from approximately 20 to 16 nm as measured by Zetasizer based on the DLS method (Figure 3). The red-colored points refer to a mixed use of magnetic stirring and ultrasonication methods. The examination of the three points in the center (all having a total processing time of 30 min) shows that ultrasonication is a more powerful tool in particle size reduction as compared with the magnetic stirring. TEM images also show that the size distribution of GNPs with a mixed use of stirring and ultrasonication is not as uniform as that with pure ultrasonication under the same processing time. Increasing the ultrasonication time produces smaller particles with more regular spherical shapes, probably because of a closer to a homogeneous reaction.


Ultrasonic-aided fabrication of gold nanofluids.

Chen HJ, Wen D - Nanoscale Res Lett (2011)

Average size of gold nanoparticles in DI water measured by a Zetasizer (blue points show the size of GNPs sonicated for 0, 30, and 45 min, and red points present the size of GNPs using a mixed magnetic stirring and ultrasonication of total 30 min).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211254&req=5

Figure 3: Average size of gold nanoparticles in DI water measured by a Zetasizer (blue points show the size of GNPs sonicated for 0, 30, and 45 min, and red points present the size of GNPs using a mixed magnetic stirring and ultrasonication of total 30 min).
Mentions: With the application of ultrasonication during the synthesis (Group B samples), the particle size becomes smaller, being reduced from approximately 20 to 16 nm as measured by Zetasizer based on the DLS method (Figure 3). The red-colored points refer to a mixed use of magnetic stirring and ultrasonication methods. The examination of the three points in the center (all having a total processing time of 30 min) shows that ultrasonication is a more powerful tool in particle size reduction as compared with the magnetic stirring. TEM images also show that the size distribution of GNPs with a mixed use of stirring and ultrasonication is not as uniform as that with pure ultrasonication under the same processing time. Increasing the ultrasonication time produces smaller particles with more regular spherical shapes, probably because of a closer to a homogeneous reaction.

Bottom Line: The ultrasonication technique is found to be a very powerful tool in engineering the size and shape of GNPs.Subsequent property measurement shows that both particle size and particle shape play significant roles in determining the effective thermal conductivity.A large increase in effective thermal conductivity can be achieved (approximately 65%) for gold nanofluids using plate-shaped particles under low particle concentrations (i.e.764 μM/L).

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Engineering and Materials Science, Queen Mary University of London, London, UK. d.wen@qmul.ac.uk.

ABSTRACT
A novel ultrasonic-aided one-step method for the fabrication of gold nanofluids is proposed in this study. Both spherical- and plate-shaped gold nanoparticles (GNPs) in the size range of 10-300 nm are synthesized. Subsequent purification produces well-controlled nanofluids with known solid and liquid contents. The morphology and properties of the nanoparticle and nanofluids are characterized by transmission electron microscopy, scanning electron microscope, energy dispersive X-ray spectroscope, X-ray diffraction spectroscopy, and dynamic light scattering, as well as effective thermal conductivities. The ultrasonication technique is found to be a very powerful tool in engineering the size and shape of GNPs. Subsequent property measurement shows that both particle size and particle shape play significant roles in determining the effective thermal conductivity. A large increase in effective thermal conductivity can be achieved (approximately 65%) for gold nanofluids using plate-shaped particles under low particle concentrations (i.e.764 μM/L).

No MeSH data available.