The influence of the fluid nature on femtosecond laser ablation properties of a SiO<sub>2/</sub>Si target and synthesis of ultrafine-grained Si nanoparticles

Author(s)
Niusha Lasemi, Christian Rentenberger, Gerhard Liedl, Dominik Eder
Abstract

Nanocrystalline silicon nanoparticles with a median crystallite size of 3-4 nm and several crystalline phases and defects (e.g.twin boundary) were produced by femtosecond laser processing of a SiO2/Si target in various organic fluids. Furthermore, a nanoscaled amorphous oxide layer and a few atomic layers of a graphite shell were detected in ethanol and 2-butanol correspondingly. The ultrafast laser pulses may manipulate nanostructures at the atomic level and generate a high density of defects; this may be correlated with significant thermal stresses on nanoparticles and rapid condensation of primary nanoparticles with high cooling rates. Size distribution width and a polydispersity index slightly increased with increasing laser fluence in ethanol. In 2-butanol, the maximum ablation volume was observed. The specific ablation rates in 2-butanol and ethanol were approximately five times higher thann-hexane. The lowest ablation efficiency inn-hexane can be associated with femtosecond laser-induced photolysis and pyrolysis of solvent molecules, as total energy deposition on the material may be reduced due to the formation of carbonaceous products. The roughened zones (average roughness of similar to 400 nm) in circumferences of the ablated craters in 2-butanol may be related to a correlation between the erosive power of the vapour bubble collapse and higher pressure at the bubble wall in relatively high dynamic viscosity fluids. Furthermore, sputtering of a pristine surface by releasing nanoparticles from the collective collapse of up-flow vapour bubbles can also contribute to the generation of roughened regions.

Organisation(s)
Physics of Nanostructured Materials
External organisation(s)
Technische Universität Wien
Journal
Nanoscale Advances
Volume
2
Pages
3991-4002
No. of pages
12
ISSN
2516-0230
DOI
https://doi.org/10.1039/d0na00317d
Publication date
09-2020
Peer reviewed
Yes
Austrian Fields of Science 2012
103042 Electron microscopy, 103018 Materials physics, 104017 Physical chemistry
Keywords
Portal url
https://ucris.univie.ac.at/portal/en/publications/the-influence-of-the-fluid-nature-on-femtosecond-laser-ablation-properties-of-a-sio2si-target-and-synthesis-of-ultrafinegrained-si-nanoparticles(d0344e9e-8e5f-4ace-8cc4-8df2ca07515b).html