Thermal-penetration-driven, record nanoparticle yield and throughput by high-power, ultraviolet nanosecond microparticle laser fragmentation.

Laser nanomanufacturing requires energy-efficient, high-throughput methods using inexpensive feedstocks and continuous operation. We demonstrate high-power ultraviolet nanosecond microparticle laser fragmentation in liquids as a controlled, high-yield, high-throughput route to ligand-free silver nanoparticles. Two synchronized 343 nm, 200 W beams enable sufficient laser fluence and single-pulse-per-volume conditions. Matching the thermal diffusion length to the microparticle diameter converts surface-confined absorption into deep photothermal heating, driving single-pulse phase explosion instead of photomechanical rupture. The productivity reaches 10 g h-1 of Ag nanoparticles <10 nm, at almost quantitative microparticle-to-nanoparticle conversion of up to 98% mass yield, achieving record throughput and mass conversion. Ionic-strength-mediated surface chemistry provides in-situ control over nanoparticle size. This establishes a scalable, green synthesis platform linking mechanistic understanding with industrial level throughput.