Size control of nanoparticles synthesized by pulsed laser ablation in liquids using donut-shaped beams
Abdel Rahman Altakroury, Oleksandr Gatsa, Farbod Riahi, Zongwen Fu, Miroslava Flimelová, Andrei Samokhvalov, Stephan Barcikowski, Carlos Doñate‐Buendía, Alexander V. Bulgakov, Bilal Gökce
Abstract
The potential to modify the size distribution of nanoparticles synthesized by pulsed laser ablation in liquids is demonstrated using a donut-shaped laser beam. In experiments on pulsed laser ablation in water of gold, yttrium oxide, and high-entropy alloy targets with both Gaussian and donut-shaped beams, we observed a significant reduction in particle size, narrowing of the size distribution width, and an improvement in sphericity when utilizing the donut-shaped laser beam. We performed time-resolved shadowgraph imaging of the laser-induced cavitation bubble, revealing a toroidal structure that overruns the ring-shaped ablation site, compared to the quasi-hemispherical bubble covering the ablation spot produced by the Gaussian beam. Based on this pioneering study, further investigation with higher temporal and spatial resolution are warranted.