Rapid synthesis of metallic and alloy micro/nanoparticles by laser ablation towards water

Abstract

A versatile method named laser ablation towards water (LATW) was developed to rapidly and simply synthesize metallic and alloy micro/nano particles, even high-entropy-alloy nanoparticles (NPs). A nanosecond pulsed laser beam passed through a transparent glass substrate, ablated its coated metallic film in the air or contacting with water, and synthesized a colloidal solution contained the micro/nano particles. In this study, Cu microparticles (MPs, Daverage = 1.8 μm), Cu MPs with Cu2O NPs, Cu2O NPs and Au NPs (Daverage = 9.5 nm) were successfully synthesized by the laser ablation of 10 μm Cu film in the air, 10 μm Cu film in the water, 200 nm Cu film in the water, 200 nm Au film in the water, respectively. The content of bimetallic NPs can be adjusted by the relative thickness ratio of bilayer film using laser ablation. Moreover, the ternary (Au-Ag-Cu), quaternary (Au-Ag-Cu-Pt), and quinary (Au-Ag-Cu-Pt-Ni) alloy NPs were also fabricated by the laser ablation of multilayer metallic film in the water. Therefore, LATW is a flexible technique for the high-effective synthesis of MPs, NPs, and various alloy NPs.