Noble metal nanoparticles produced by nanosecond laser ablation

• Published in: Applied physics. A, Materials science & processing Vol. 104; no. 3; pp. 829 - 837
• Main Authors: Ossi, P. M., Neri, F., Santo, N., Trusso, S.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-09-2011
• Subjects: Ablation; Arrays; Characterization and Evaluation of Materials; Condensed Matter Physics; Dispersions; Laser ablation; Machines; Manufacturing; Nanoparticles; Nanostructure; Nanotechnology; Optical and Electronic Materials; Physics; Physics and Astronomy; Plumes; Processes; Surfaces and Interfaces; Thin Films; Surface Enhance Raman Scatter Substrate; Transmission Electron Microscopy Picture; Surface Enhance Raman Scatter; Noble Metal Nanoparticles; Plasma Expansion
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-011-6422-0

Silver and gold thin films were deposited by pulsed laser ablation in a controlled Ar atmosphere at pressures between 10 and 100 Pa. Different morphologies, ranging from isolated nanoparticle arrays up to nanostructured thin films were observed. Fast imaging of the plasma allowed deducing the expansion dynamics of the ablated plume. Plasma velocity and volume were used together with the measured average ablated mass per pulse as input parameters in a model to estimate the average size of nanoparticles grown in the plume. The nanoparticle size is expected to decrease from 4 nm down to 1 nm with decreasing Ar pressure between 100 and 10 Pa: this was confirmed by transmission electron micrographs which indicate a reduced dispersion of particle size over narrow size ranges. The production of substrates for surface enhanced Raman scattering whose performances critically depend on nanoparticle size, shape, and structure is discussed.