46 - Modification of Silver Nanowire Surfaces with PVP and L-Cysteine
St. Olaf College
Bulk objects made of transition metals sometimes have a layer of oxidized metal (i.e. rust, patina, or tarnish) covering the surface due to reactions with air and water. While this layer degrades the object slightly, it also protects the inside metal to further oxidation. On the nano scale, a surface€s ability to protect its reactive metal core is even more important, as a single nanoparticle may only be comprised of a few thousand atoms. The reaction between exposed nanoparticle surfaces and air or water may cause them to dissolve into metal ions, a process detrimental for some applications and necessary for others. The goal of my work is to synthetically modify surface compositions of silver nanowires with coating agents PVP, a water soluble polymer, and L-cysteine in order to control the rate of nanoparticle dissolution. Both coating agents exhibit similar binding interactions with silver surfaces but differ in molecule size and binding strength. Tuning the thickness and thoroughness of the nanowire€s coating by using these coating agents in varying ratios may help to better protect or expose the metal core for a variety of applications. My work additionally explores mechanistic features of anisotropic (one-directional) silver nanowire growth.