Prof. Byungkwon Lim and two doctorate level students, Hwansu Sim and Shingyu Bok, successfully demonstrated a new synthesis of fabrication of Silver (Ag) Nanowires (NWs) without the use of any organic stabilizers.

Ag NWs have attracted great interest owing to their high electrical conductivity, solution processability, and potential for applications in highly conductive transparent or stretchable electrodes.

However, organic capping molecules for the production of Ag NWs introduce insulating layers around each nanowire, thus dramatically increasing contact resistance between them and reducing efficiency in electrode applications. A typical procedure for removing organic capping layers from the NWs surface involves many cycles of the precipitation and re-dispersion of NWs in a good solvent for capping molecules, which is tedious and time consuming.

The research team resolved the problems by using a little amount of metal salt instead of an organic stabilizer. The heterogeneous nucleation and growth of Ag NWs initially formed AgCl particles, combined with oxidative etching of unwanted silver nanoparticles, resulted in the selective formation of long NWs with an average length of about 40 mm in the absence of a capping or stabilizing effect provided by surface-adsorbing molecules. These organic-stabilizer-free Ag NWs were directly used for the fabrication of high-performance transparent or stretchable electrodes without a complicated process for the removal of capping molecules from the NW surface.

This research was published in the journal Angewandte Chemie under the subject name of Organic-Stabilizer-Free Polyol Synthesis of Silver Nanowires for Electrode Applications.