Influence of intensity distribution of laser beam on the properties of nanoparticles obtained by laser ablation of solids in liquids

TL;DR

This study demonstrates that controlling the laser beam's intensity distribution during laser ablation in liquids influences the size and properties of the resulting nanoparticles, with experimental validation using different laser types and targets.

Contribution

It introduces a method to modulate nanoparticle properties by adjusting the laser beam profile during ablation, providing new control over nanoparticle synthesis.

Findings

Nanoparticle size depends on laser beam spatial profile

Different laser wavelengths and pulse durations were used

Characterization confirmed property variations based on beam modulation

Abstract

Control over the properties of nanoparticles obtained by laser ablation in liquids is experimentally demonstrated via modulation of the beam intensity profile on the target. Mask projection scheme was used with either a copper laser (wavelength of 510. 6 nm, pulse duration of 10ns) or with a Ti:sapphire laser (wavelength of 800 nm and pulse duration of 200 fs). Si and ZnSe were chosen as target materials. Obtained nanoparticles were characterized using Transmission Electron Microscopy (TEM), optical absorption spectroscopy and photoluminescence. It was shown that that size of Si nanoparticles depends on the spatial profile of the laser beam.