Evolution of the distribution function of Au nanoparticles in a liquid under the action of laser radiation

Fragmentation of nanoparticles in a liquid under the action of pulsed laser heating is studied theoretically and experimentally. Fragmentation is simulated by solving the kinetic equation for the nanoparticles size distribution function, taking into account the temperature dependence of the thermophysical parameters of the medium. It is shown that fragmentation occurs after separation of smaller fragments from a molten nanoparticle. The simulation results are in good agreement with experimental data obtained in the fragmentation of gold nanoparticles irradiated in water by a copper vapour laser with a peak radiation intensity of about 10⁶ W cm^-2.