0000000001191544
AUTHOR
Spyridon Korkos
Elongation and plasmonic activity of embedded metal nanoparticles following heavy ion irradiation
Shape modification of embedded nanoparticles by swift heavy ion (SHI) irradiation is an effective way to produce nanostructures with controlled size, shape, and orientation. In this study, randomly oriented gold nanorods embedded in SiO2 are shown to re-orient along the ion beam direction. The degree of orientation depends on the irradiation conditions and the nanorod's initial size. SHI irradiation was also applied to modify spherical metallic nanoparticles embedded in Al2O3. The results showed that they elongate due to the irradiation comparably to those embedded in SiO2. Metallic nanostructures embedded in dielectric matrices can exhibit localized surface plasmon (LSP) modes. The elongat…
Nanorod orientation control by swift heavy ion irradiation
Highly energetic ions have been previously used to modify the shape of metal nanoparticles embedded in an insulating matrix. In this work, we demonstrate that under suitable conditions, energetic ions can be used not only for shape modification but also for manipulation of nanorod orientation. This observation is made by imaging the same nanorod before and after swift heavy ion irradiation using a transmission electron microscope. Atomistic simulations reveal a complex mechanism of nanorod re-orientation by an incremental change in its shape from a rod to a spheroid and further back into a rod aligned with the beam. Highly energetic ions have been previously used to modify the shape of meta…
Size dependent swift heavy ion induced Au nanoparticle elongation in SiO2 matrix
The elongation of spherical Au nanoparticles embedded in SiO2 under swift heavy ion (SHI) irradiation is an extensively studied phenomenon. The use of a TEM grid as a substrate facilitates the identification of the same nanoparticle before and after the irradiation. Since the underdensification of SiO2 inside the ion track plays a key role, the elongation is sensitive to the matrix material properties. Therefore, we studied the elongation process of SHI irradiated Au spherical nanoparticles of various diameters (5–80 nm) embedded either in atomic layer deposition (ALD) or plasma-enhanced chemical vapor deposition (PECVD) SiO2. The results show that a different elongation ratio is achieved d…