Optical properties of femtosecond laser-synthesized silicon nanoparticles in deionized water
Authors: Intartaglia R., Bagga K., Brandi F., Das G., Genovese A., Di Fabrizio E., Diaspro A.
Autors Affiliation: Italian Institute of Technology (IIT), via Morego 30, 16152 Genoa, Italy; BIONEM Lab, University Magna Graecia, Viale Europa Catanzaro, Italy
Abstract: Silicon nanoparticles were prepared by ultrafast laser ablation of a silicon target in deionized water. The nanoparticles were characterized by using optical absorption, Raman spectroscopy, and transmission electron microscopy. The mean size is found to vary from 60 to 2.5 nm in the absence of any reducing chemical reagents, decreasing the pulse energy value. High-resolution transmission electron microscopy together with Raman spectroscopy confirms the crystalline structure of the generated silicon nanoparticles. The energy confinement of carriers which is evaluated from optical experiments varies from 90 to 550 meV when the mean nanoparticles size decreases from 60 to 2.5 nm. In particular, the evaluated nanoparticle sizes from optical analysis and the LCAO theoretical model are found in agreement with transmission electron microscopy and Raman measurements for the silicon nanoparticles with a size less than 6 nm. Finally, we present stability studies which show that the smallest nanoparticles aggregate over time.
Journal/Review: JOURNAL OF PHYSICAL CHEMISTRY C
Volume: 115 (12) Pages from: 5102 to: 5107
More Information: This work was supported by the Italian Institute of Technology. The authors gratefully acknowledge the technical help of Marco Scotto d\’Abbusco.KeyWords: e da rivista: Chemical reagents; Crystalline structure; Energy confinement; Femto-second laser; Mean size; Nanoparticle sizes; Optical absorption; Optical analysis; Optical experiments; Pulse energies; Raman measurements; Silicon nanoparticles; Silicon targets; Stability study; Theoretical models, Ablation; Absorption spectroscopy; Deionized water; Electron microscopy; Nanoparticles; Optical properties; Raman scattering; Raman spectroscopy; Ultrafast lasers, High resolution transmission electron microscopyDOI: 10.1021/jp109351tCitations: 70data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2019-11-17References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here