Dynamics of pulsed laser ablation in high-density carbon dioxide including supercritical fluid state

Abstract

To gain a better understanding of pulsed laser ablation (PLA) processes in high-density fluids, including gases, liquids, and supercritical fluids (SCFs), we have investigated the PLA dynamics in high-density carbon dioxide (CO2) using a time-resolved shadowgraph (SG) observation method. The SG images revealed that the PLA dynamics can be categorized into two domains that are separated by the gas-liquid coexistence curve and the Widom line, which forms a border between the gaslike and liquidlike domains of an SCF. Furthermore, a cavitation bubble observed in liquid CO2 near the critical point exhibited a particular characteristic: the formation of an inner bubble and an outer shell structure. The results indicate that the thermophysical properties of the reaction field generated by PLA can be dynamically tuned by controlling the solvent temperature and pressure, particularly near the critical point.

A hierarchical view on material formation during pulsed-laser synthesis of nanoparticles in liquid

“…Therefore, a singular collapse and subsequent expansion as in sonoluminescence cannot be expected. Internal structure has been seen previously 19 48 . In particular in CO 2 matrix close to the critical point the continuous heat supply from the target creates additional voids and dephasing of the bubble dynamics.…”

ZnO nanorods prepared via ablation of Zn with millisecond laser in liquid media

“…The recent use of high pressures, i.e. ablating in pressurized cells, permits to expand the technique and allows for more control over the product [17][18][19][20].…”

Production of TiO2 nanoparticles in different phases and shapes by using PLA and hydrothermal method

“…Laser ablation of the solid targets in the liquid has attracted attention for a last decade because of its potential to produce small, monodispersed nanoparticles with complex compositions [7]. Pulsed laser ablation (PLA) is process of ablating material from a target surface by using irradiation with ultra-short laser to form the high temperature plasma [8]. Nanotechnology deals with the nanoparticles production, particularly synthesis and processing of metals, metal carbides, semiconductors, and metal oxides [9].…”