Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9809728 | Surface and Coatings Technology | 2005 | 5 Pages |
Abstract
Negative ion implantation has been applied to polymers in order to modify the surface and to fabricate nanoparticles. Metal nanoparticles in the vicinity of a polymeric surface are promising for biomedical applications as well as nonlinear optical applications. Substrates of polymethyl methacrylate (PMMA) were implanted with Agâ and Cuâ of 60 keV at 3 μA/cm2 up to 3Ã1017 ions/cm2. Optical absorption spectra of the implanted PMMA were measured in a photon range from 0.5 to 4.5 eV. A peak of surface plasmon resonance (SPR) emerges in the absorption spectra above about 1Ã1017 ions/cm2, both for the Agâ and Cuâ cases. A coexisting absorption slope, due mostly to defects, increases but tends to saturate with ion fluence. The SPR peak of Ag-implanted PMMA is much broader than that of the Cu-implanted one. Corresponding to the SPR spectra, metal nanoparticles are observed by cross-sectional TEM. With increasing ion fluence, the Ag nanoparticles spread out towards the surface, in contrast to the localized Cu nanoparticles. The results demonstrate that metal nanoparticle fabrication in polymers is capable by using appropriate low-energy ions and provides a variety of spatial distributions dependent on ion species and fluence. In particular, Agâ ion implantation fabricates surface-exposed/gradient nanoparticles, which are suitable for biomedical applications such as anti-microbial effects.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Nanotechnology
Authors
H. Boldyryeva, N. Umeda, O.A. Plaksin, Y. Takeda, N. Kishimoto,