Technology

This is our proprietary nanoparticle synthesis method. A high-power pulsed laser is focused into a solution containing metal ions as precursors. Physicochemical reactions near the focal point generate nanoparticles. Unlike conventional chemical reduction methods, this process requires no reducing agents, eliminating the need for subsequent separation and purification associated with those agents. By using a solution containing multiple types of metal ions, we can control the composition of fully solid-solution alloys that are difficult to produce under conventional thermal equilibrium conditions. We can also modify nanoparticle surfaces, select dispersion solvents, and deposit nanoparticles onto supports.

Pulsed-laser ablation in liquids is a nanoparticle synthesis technique with a history of approximately 20 years and growing use worldwide. Laser irradiation is focused onto a solid target immersed in a liquid or into a colloidal dispersion of solid particles. The resulting ablation process produces particles smaller than the starting material. Femtosecond laser pulses, with their nonthermal processing characteristics, can produce fine particles while preserving the crystal structure of the original material. We have found that, when a colloidal dispersion contains multiple types of solid particles, alloying can occur during particle size reduction by ablation. A patent application is pending. This technique is expected to reduce particle size and improve the properties of materials already in practical use.