Investigation of the laser-induced breakdown plasma, acoustic vibrations and dissociation processes of water molecules caused by laser breakdown of colloidal solutions containing Ni nanoparticles

Abstract

In this work the process of optical breakdown under laser irradiation by nanosecond pulses with an energy of 650 mJ of aqueous solutions of Ni nanoparticles is investigated. A monotonic change in the number of breakdowns, the average distance between closest breakdowns, the average plasma size of an individual breakdown, the luminosity of a plasma flash, the intensity of acoustic signals, and the rate of formation of dissociation products - O2, H2, OH•, and H2O2 with an increase in the irradiation time was established. With an increase in the concentration of nanoparticles, the measured values change non-monotonically. The maximum luminosity of a plasma flash is observed at a nanoparticle concentration of 109 NP/ml and 1010 NP/ml and reaches 350 cd/m2. The maximum pressure at the shock front is 1.5–2 MPa at a nanoparticle concentration of 1010 NP/ml. The maximum rates of generation of O2, H2, OH• and H2O2 are observed at concentrations of 109 NP/ml and 1010 NP/ml. Correlation analysis of the studied physicochemical phenomena shows that the formation of molecular gases is associated with acoustic processes, and the formation of radical products and hydrogen peroxide correlates with the physicochemical properties of plasma.

Laser-Induced Optical Breakdown of an Aqueous Colloidal Solution Containing Terbium Nanoparticles: The Effect of Oxidation of Nanoparticles

“…30 The physicochemical characteristics of optical breakdown plasma depend to a large extent on the concentration of nanoparticles (Figure 4). The concentration dependence was previously shown for gold, 8 nickel, 31 iron, molybdenum, and zirconium 32 nanoparticles. The effect of the degree of oxidation of nanoparticles on the physicochemical characteristics of optical breakdown plasma has not been studied before.…”

Effect of Laser-Induced Optical Breakdown on the Structure of Bsa Molecules in Aqueous Solutions: An Optical Study

“…For example, when the protein concentration changes by five orders of magnitude, the number of optical breakdowns caused by a single laser pulse increases by fewer than four times ( Figure 1 a). For comparison, when the concentration of metal nanoparticles (Au and Ni) changes by one order of magnitude, the number of optical breakdowns caused by a single laser pulse increases by a factor of three (Au) [ 28 ] or seven (Ni) times [ 29 ]. A change in the protein concentration in aqueous solution by five orders of magnitude changes the average luminescence intensity of individual optical breakdown by fewer than two times ( Figure 1 b).…”

“…A change in the protein concentration in aqueous solution by five orders of magnitude changes the average luminescence intensity of individual optical breakdown by fewer than two times ( Figure 1 b). In the case of metallic nanoparticles, a change in the average luminescence intensity of individual optical breakdown by less than a factor of two is usually observed when the concentration changes by one order of magnitude [ 29 ]. The average distance between optical breakdowns caused by a single laser pulse has little dependance on the protein concentration ( Figure 1 c).…”

Comparative Analysis of the Cytotoxic Effect of a Complex of Selenium Nanoparticles Doped with Sorafenib, “Naked” Selenium Nanoparticles, and Sorafenib on Human Hepatocyte Carcinoma HepG2 Cells

“…The size of nanoparticles was characterized using a DC24000 analytical centrifuge (CPS Instruments, Prairieville, LA, USA). Nanoparticle concentration and hydrodynamic radius were evaluated using Zetasizer Ultra Red Label (Malvern, UK) [ 70 ]. It was found that the resulting preparation of selenium nanoparticles has a monomodal size distribution ( Figure 10 ).…”