Highly foldable transparent conductive films composed of silver nanowire junctions prepared by chemical metal reduction

A simple method is demonstrated to improve the folding reliability and sheet resistance of silver nanowire (Ag NW)-based transparent conductive films (TCFs) without overcoated layers or complicated processes. As-coated Ag NW film is immersed in a silver-surrounded solution, in which the silver was reduced by Tollen's reagent. Therefore, the reduced silver can be deposited on the surface and crossing of Ag NWs to form a weld-like junction and bind the Ag NWs together, hence decreasing the contact resistance of Ag NW structure at wire-to-wire junctions by increasing the contact surface area. Compared with original Ag NW TCFs, this Ag NW junction structure not only shows compatibility with conventional wet processes, but also demonstrates outstanding flexibility, even when the entire film is folded. This could be attributed to the robustly weld-like wire-to-wire junction of Ag NWs, which enhances its mechanical characteristics. The results demonstrated the feasibility of this alternative approach for the development of an effective low-power-consumption route for fabricating foldable transparent electrodes. Moreover, the results also indicated the practicability of applying this foldable transparent electrode in the fabrication of highly flexible and wearable optoelectronic devices. (papers)