[Paper Review] Size distribution of Au NPs generated by laser ablation of a gold target in liquid with time-delayed femtosecond pulses

Emanuel Axente, M. Barberoglou+6 more|arXiv (Cornell University)|Aug 2, 2010

Laser-Ablation Synthesis of Nanoparticles1 references3 citations

TL;DR

This study investigates how time-delayed femtosecond laser pulses affect the size distribution, optical properties, and formation kinetics of gold nanoparticles (Au NPs) produced via laser ablation of a gold target in ethanol. By varying the delay between pulses, the researchers observed tunable nanoparticle size distributions, shifts in plasmon resonance, and altered generation rates, demonstrating precise control over nanoparticle synthesis through pulse timing.

ABSTRACT

The influence of delay-time between two sequential femtosecond pulses on the properties of nanoparticles obtained via laser ablation of gold in ethanol has been studied. The morphological and optical properties of the nanoparticles attained were characterized using high resolution transmission electron microscopy and UV_Vis absorption spectroscopy, respectively. Furthermore, the size distribution of nanoparticles was determined by means of a centrifugal sedimentation particle size analyzer. It is found that the time delay variations lead to corresponding changes in size distribution, plasmon resonance position as well as the rate of nanoparticles generation.

Motivation & Objective

• To investigate the influence of time delay between two femtosecond laser pulses on the synthesis of gold nanoparticles in liquid.
• To characterize the morphological and optical properties of the generated nanoparticles.
• To determine how pulse delay affects the size distribution and generation rate of Au NPs.
• To establish a method for tuning nanoparticle characteristics through precise control of laser pulse timing.

Proposed method

• Laser ablation of a gold target in ethanol using time-delayed femtosecond pulses with variable delay intervals.
• High-resolution transmission electron microscopy (HRTEM) for morphological characterization of the synthesized nanoparticles.
• UV-Vis absorption spectroscopy to analyze the plasmon resonance properties of the nanoparticles.
• Centrifugal sedimentation particle size analyzer to quantitatively determine the size distribution of the nanoparticles.
• Systematic variation of the time delay between the two pulses to study its effect on nanoparticle formation.

Experimental results

Research questions

• RQ1 How does the time delay between two femtosecond laser pulses affect the size distribution of gold nanoparticles formed in ethanol?
• RQ2 What is the impact of pulse delay on the plasmon resonance peak position of the generated gold nanoparticles?
• RQ3 How does the delay between pulses influence the rate of nanoparticle generation during laser ablation?
• RQ4 Can the morphological and optical properties of the nanoparticles be systematically tuned by adjusting the pulse delay?

Key findings

• Variation in the time delay between femtosecond pulses leads to measurable changes in the size distribution of the generated gold nanoparticles.
• The plasmon resonance peak position shifts systematically with changes in pulse delay, indicating tunable optical properties.
• The rate of nanoparticle generation is dependent on the time delay, with distinct trends observed across different delay intervals.
• The size distribution is not monodisperse and shows a broad distribution that shifts in response to pulse delay, indicating dynamic nucleation and growth processes.