Positioning of Carbon nanostructures on metal surfaces using laser acceleration and the Raman analyses of the patterns

Abstract

The laser-induced acceleration of nanoparticles using intense light irradiation was used for positioning and ordering of carbon nanomaterials to form periodical surface structures. Such systems are of interest for different nanotechnology applications. The nanodiamond with averaged size 100 nm, and fullerene (C60) suspended in distilled water were accelerated using high focused laser beam and attached onto metal surface of silver and gold thin films evaporated on Si substrate. The laser was operating both in CW and femtosecond modes with the wavelength of ∼800 nm, pulse duration 150 fs, and average laser power of 300-600 mW. In case of pulse irradiation the repetition rate of 76 MHZ was applied. The nanoparticles were positioned on the metal surface in accordance with a predetermined program to allow patterning of the nanoparticles. The positioning was analyzed for different treatment conditions and compared to the calculated data. To investigate the obtained nanoparticles/metal structures, surface-enhanced Raman scattering (SERS) was used utilizing its high sensitivity on the local properties of the nanostructures. SERS allows the observing of carbon nanostructures with their characteristic peculiarities, such as blinking effect and selective enhancement. Here we try to explain the spectral and spatial peculiarities occurring during the laser acceleration process and the interaction of attached carbon nanostructures with metal surface.