Dependence of the size of copper nanoparticles on laser energy synthesized by pulsed laser ablation
Prahlad K. Baruah, Ashwini K. Sharma, Alika Khare
Volume 2, Issue 4, Page 264-268, Year 2017 | DOI: 10.5185/amp.2017/412
Keywords: Laser ablation, copper nanoparticles, surface plasmon resonance, nanoparticle size, plasmon bandwidth.
Abstract: In this paper, the effect of incident laser energy on the localized surface plasmon resonance (LSPR) and size of copper (Cu) nanoparticles (NPs) synthesized via pulsed laser ablation of copper in distilled water (DW) is reported. The absorption spectra show plasmon peak in the visible spectral region. The increase in the laser energy from 30 mJ to 70 mJ of the second harmonic of a Q-switched Nd:YAG laser induces a blue shift in the plasmon peak from 627 nm to 617 nm along with its broadening from 180 nm to 242 nm, respectively. These observations have been explained on the basis of the effect of the small size of the NPs formed. The Transmission electron microscope (TEM) substantiates these results as it shows the decrease in the average particle size of the NPs from ~20 nm to ~7 nm with the increase in the incident laser energy from 30 mJ to 70 mJ, respectively. By merely increasing the laser energy, a size-dependent LSPR has been achieved and this can be used as an effective way to control the size of Cu NPs and hence LSPR. Copyright © 2017 VBRI Press