Characterization of self-assembled silver nanoparticle ink based on nanoemulsion method

Area of Science:

• Materials Science
• Nanotechnology
• Chemistry

Background:

• Developing stable and pure silver nanoparticle (AgNP) inks is crucial for advanced electronic applications.
• Traditional synthesis methods often face challenges with dispersion, purity, and controlled particle size.

Purpose of the Study:

• To synthesize a well-dispersed, high-purity AgNP ink using an emulsion-based approach.
• To investigate the role of polyoxyethylene (20) sorbitan monooleate (Tween 80) in the synthesis and stabilization of AgNPs.
• To characterize the properties of the synthesized AgNPs, including size, stability, and conductivity.

Main Methods:

• Synthesis of a silver nitrate (AgNO3) emulsion by blending aqueous AgNO3 with a liquid paraffin solution containing Tween 80 and sorbitan monooleate (Span 80).
• Sintering of the emulsion at approximately 60°C to produce AgNPs.
• Characterization using thermogravimetric analysis (TGA), X-ray diffraction (XRD), dynamic light scattering (DLS), and ultraviolet-visible (UV-Vis) spectroscopy.

Main Results:

• A stable AgNP ink was successfully synthesized, yielding AgNPs with diameters ranging from 8.6 to 13.4 nm.
• Tween 80 acted as a surfactant, reductant, and stabilizer, facilitating AgNP formation through an autoxidation process.
• The synthesized AgNPs exhibited high purity (Ag0) and high conductivity.
• Decreasing water content and increasing surfactant ratio or AgNO3 concentration led to smaller emulsion droplet and AgNP sizes.

Conclusions:

• The developed emulsion-based method provides a facile route to high-purity, stable, and conductive silver nanoparticles.
• Tween 80 plays a critical multifunctional role in the synthesis and stabilization of AgNPs.
• The particle size of AgNPs can be effectively tuned by adjusting emulsion composition and precursor concentration.