Production of Oxidation-Resistant Cu-Based Nanoparticles by Wire Explosion

Area of Science:

• Materials Science
• Nanotechnology
• Electrochemistry

Background:

• Commercially available conductive inks face limitations in performance and cost, hindering printed electronics.
• Developing affordable and high-performance conductive inks is crucial for advancing printed electronics technology.

Purpose of the Study:

• To establish a simple, low-cost, and eco-friendly method for producing metallic nanoparticles for conductive inks.
• To investigate the use of aqueous metal wire explosion for synthesizing copper (Cu) and Cu alloy nanoparticles.
• To enable direct printing of conductive lines from these nanoparticles without post-treatment.

Main Methods:

• Aqueous explosion of metal wires (Cu and Cu alloys) to generate metallic nanoparticles.
• Addition of 0.2 M ascorbic acid to the aqueous medium to prevent copper oxide shell formation.
• Preparation of Cu alloy nanoparticles from pre-alloyed wires or by twisting wires of different metals.
• Characterization of nanoparticle properties and conductivity of printed lines.

Main Results:

• The aqueous explosion method successfully produced Cu and Cu alloy nanoparticles.
• Addition of ascorbic acid prevented Cu2O shell formation, allowing direct printing of conductive lines.
• Cu nanoparticles alloyed with Sn, Ag, and Ni exhibited electrical conductivity comparable to pure Cu.
• Alloyed Cu nanoparticles demonstrated enhanced stability, maintaining conductivity after 24 hours at 85°C and 85% RH, unlike pure Cu.

Conclusions:

• Aqueous metal wire explosion offers a scalable and cost-effective route to high-performance conductive nanoparticles.
• The developed method facilitates the creation of stable, conductive inks for printed electronics applications.
• The use of ascorbic acid is key to achieving printable, post-treatment-free conductive lines.