A systematic and effective research procedure for silver nanowire ink

Silver nanowire (AgNW) ink has great influence on the performance of the resulting AgNW-based conductive film, especially for the large-scale roll-to-roll processed films. However, AgNW inks made by researchers are almost immature because there is not a clear research procedure for the development of qualified inks. In this work, electric double layer model, Young equation, bubble theory, percolation theory, Rhodes & Orchäd equation, Kelvin equation and other theoretical models were introduced successively to describe those processes which additives in inks should adjust. Based on the guidance of these theories, additives were determined successively and an optimized light grey ink with the composition of 0.4% AgNW + 0.2% 2-amino-2-methyl-1-propanol + 0.01% Zonyl FSO-100 + 1.5% diacetone alcohol + 5% 1,4-dioxane + 92.89% isopropyl alcohol was obtained. Except for trace amount of Zonyl FSO-100, other additives could be easily eliminated at low temperature (110 °C), which could retain the original properties of AgNW furthest and greatly lower the dosage of AgNW in inks. Based on this ink, excellent AgNW/PET composite film was prepared. The sheet resistance, transmittance and haze of this film were 29.5 Ω/sq, 88.9% and 1.49% respectively. Finally, touch screens (180 mm × 105 mm) and tablets (10 inches) were prepared from our films and showed good performance. These results demonstrated that excellent AgNW ink could be developed through our research procedure. Our studies not only produce an excellent AgNW ink, but also provide a systematic research procedure and series of theoretical models for many kinds of conductive inks.