Gram Scale Synthesis of Pure Ceramic Nanoparticles by Laser Ablation in Liquid

Abstract

Scale-up criteria of laser ablation in the liquid phase with nanosecond pulses is studied for efficient generation of pure ceramic nanoparticles in an aqueous environment. Besides high laser fluence and low height of the applied liquid layer, specific pulse overlap and defined laser repetition rate are required for significant enhancement in nanoparticle productivity. The ablation rate increases by 350% by reducing the liquid film from 8 mm to 2.5 mm owing to reduced absorption and scattering of the incident laser beam by previously ablated nanoparticles. The controlled interpulse distance yields a further increase in material removal rate by another 300% compared to machining in the pulse overlap mode. The residual cavitation bubble from the previous laser pulse and the dispersed nanoparticle interaction with the following laser pulse and optimized temperature gradient in the lattice of the target are assumed to alter productivity. This hypothesis is confirmed by varying the repetition rate with equal laser fluence and pulse overlap, which causes a drastic rise in nanoparticle productivity by a factor of 65. A maximum corundum nanoparticle productivity of 1.3 g/h with Feret particle size of 30 nm is gained by 18.5 W of focused laser power at 4 kHz of repetition rate, providing 125 µm interpulse distance and liquid flow.

Optimisation of GaAs nanocrystals synthesis by laser ablation in water

“…Therefore, more absorption and/or scattering of the next pulse results in decreasing of the ablation rate. Then, decreasing the contribution of single pulses by increasing the pulse repetition rate is expected and in accordance with the pervious experimental reports [13]. An important parameter that has considerable effects on the target surface condition and the resultant amount of ablation rate [13,14], as shown in Figure 4, is the overlapping factor (O f ) that is calculated as [15] …”

Laser assisted synthesis of carbon nanoparticles with controlled viscosities for printing applications

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Synthesis of hybrid microgels by coupling of laser ablation and polymerization in aqueous medium

“…Hence, wet chemical or physical methods could be the method fabricating the aqueous colloids. In contrary to chemical precipitation of sol-gel method, pulsed laser ablation in liquid has been demonstrated as a method that allows to fabricate nanoparticles in water and organic liquids free of impurities 52,53 even in gram scale, 54 in particular, if ultrashort laser pulses are used. 55,56 In this study, we aim to combine NP synthesis using laser ablation in liquids with using the synthesized colloidal NPs in the polymerization process to form hybrid microgels.…”