Synthesis of dimension-controlled silver nanowires for highly conductive and transparent nanowire films

High-quality silver (Ag) nanowires with specific dimensions were synthesized by a polyol method with detailed control of the synthesis conditions. For the same amount of AgNO₃, the Ag nanowire density became higher as the nanowire diameter decreases and the length increases. This trend was replicated in Ag nanowire films coated on poly(ethylene terephthalate) films and higher densities of Ag nanowires and their junctions were observed in thinner and shorter nanowire networks. Nanowire films with a low sheet resistance (<100 Ω sq^-1) and a high transmittance (>90%) resulted from thin, long Ag nanowires. A modified percolation model, which emphasized the importance of the nanowire junction density, was in good agreement with the experimental observations. Meanwhile, long Ag nanowires were found to be undesirable in respect of their uniform coating over a large area. These results offer important design rules of Ag nanowires for highly conductive and transparent nanowire films.