Triggering the Sintering of Silver Nanoparticles at Room Temperature

TLDR

The study presents a new approach to achieve room‑temperature sintering of metallic nanoparticles, enabling high‑conductivity conductive patterns through printing of silver nanoparticle inks. The authors found that silver nanoparticles spontaneously coalesce with oppositely charged polyelectrolytes at room temperature, producing conductive patterns on plastic and paper with about 20 % of bulk silver conductivity, sufficient for devices such as inkjet‑printed electroluminescent displays.

Abstract

A new approach to achieve coalescence and sintering of metallic nanoparticles at room temperature is presented. It was discovered that silver nanoparticles behave as soft particles when they come into contact with oppositely charged polyelectrolytes and undergo a spontaneous coalescence process, even without heating. Utilizing this finding in printing conductive patterns, which are composed of silver nanoparticles, enables achieving high conductivities even at room temperature. Due to the sintering of nanoparticles at room temperature, the formation of conductive patterns on plastic substrates and even on paper is made possible. The resulting high conductivity, 20% of that for bulk silver, enabled fabrication of various devices as demonstrated by inkjet printing of a plastic electroluminescent device.