Synthesis and characterization of copper nanowire/polymer composite transparent electrodes

Abstract

Transparent conducting films (TCFs) are optically transparent and electrically conductive in thin lay-ers. Indium tin oxide (ITO) is traditionally used for organic solar cells and touch screen panels (TSPs) as transparent electrodes. But it is scarce, brittle and expensive. For these reasons, some alternative materials, including carbon nanotubes (CNTs), graphene, and metal nanowires, have been studied to improve the flexi-bility and decrease the price. Metal nanowire film are promising substitute materials due to their similar transmittance and conductivity compared with ITO. Copper nanowires (Cu NWs) are promising candidate materials to replace ITOs and Ag NWs in TE applications due to similar to silver in conductivity and low price. In this thesis, Cu NWs were synthesized by thermal decomposition and galvanic displacement method. A de-tail parametric study was conducted to find the relationship between morphology of NWs and the parameter such as temperature, stirring speed and molar ratio of $Ni(acac)_2$ to $CuCl_2 \cdot 2H_2O$. And the thinner and longer NWs were gained at low temperature and slow stirring speed, which is 33.7 nm and $66.9 \mu m$ corresponding to diameter and length, respectively. I found that the relationship between the morphology of Cu NWs and opti-cal, electrical properties of Cu NW TEs. The best performances such as sheet resistance and transmittance were $100 \Omega/sq$ and 91 % at 550 nm, respectively. Finally, to develop adhesion, roughness and stability of Cu NW TEs, I fabricated by Cu NW/polymer composite TEs.