Ultrathin Copper Nanowire Synthesis with Tunable Morphology Using Organic Amines for Transparent Conductors

High-quality monodispersed copper nanowires with an ultrathin diameter of 13.5 nm, lengths up to 30 μm (aspect ratio >104) were successfully synthesized by a facile and controllable hydrothermal reduction procedure. The synthesis utilized glucose in the presence of hexadecylamine (HDA) and octadecylamine (ODA) as the capping agents. The copper decahedra nanoparticles with a low-surface-energy {111} plane formed pentatwinned one-dimensional nanowires, which was exactly verified by selected-area electron diffraction. Furthermore, the diameter and relative film conductivity of copper nanowires are sensitive to the HDA/ODA molar ratio. The conductor film made of the high-quality and ultrathin copper nanowires shows high transmittance and low resistance (83.83%, 61 Ω/□), exhibiting great potential in the applications of nanofabrication, transparent and flexible conductors, organic light-emitting diodes, and more.