Parallel Diffractive Multi-Beam Pulsed-Laser Ablation in Liquids Toward Cost-Effective Gram Per Hour Nanoparticle Productivity

Nanoparticles (NPs) generated by pulsed-laser ablation in liquids (PLAL) have benefited many key applications due to their versatility, enlarged surface area, and high purity. However, scaling up NPs production represents one of the main requisites to commercialize this technology. The established upscaling strategy demands high power and repetition rate laser source with fast scanning systems, which are not widely available and costly. Herein, a cost-effective alternative is proposed, the addition of static diffractive optical elements to achieve parallel processing through the multi-beam PLAL (MB-PLAL). In MB-PLAL, the optimum repetition rate is reduced to compensate laser energy splitting, hence achieving a higher interpulse distance, reducing pulse shielding, and increasing NPs productivity. MB-PLAL with 11 beams reached a factor 4 productivity increase for iron-nickel alloy (Fe50Ni50) NPs compared to the single-beam setup (0.4-1.6 g h-1), and a factor 3 increase for gold (Au) NPs (0.32-0.94 g h-1). The scalability of the proposed MB-PLAL technique setup is confirmed by Au and Fe50Ni50 NPs productivity experiments using 1, 6, and 11 beams, showing a linear increase in productivity. A fourfold increase of iron-nickel nanoparticles production rate through pulsed-laser ablation in liquid (PLAL) is observed with the integration of 11-beam splitter diffractive optical element in the PLAL system. The method is termed as multi-beam PLAL and it is proposed as an economical approach to increase the productivity of PLAL method for its prospective use in the industry.image (c) 2024 WILEY-VCH GmbH