Electroactive Triphenylamine-Based Polymer Films as Passivation Layers for Improving Electrochemical Oxidation Stability of Silver Nanowires

Silver nanowires (AgNWs) have emerged as a greater promising material for transparency-based electrodes compared to indium-tin-oxide (ITO) electrodes because of the tunable figures of merit, large-scale processability, and flexibility. However, they still suffered from a crucial problem of instability under the thermal condition, mechanical stimuli, and particularly sustained electrical currents, which is a challenge persisting to date. Here, we demonstrate the improved electrochemical stability of AgNWs by a simple cost-effective electroactive triphenylamine (TPA)-based polymer film as a passivation layer onto the AgNW networks. The AgNW/TPPA hybrid electrode could not only enhance the overall performance including electrical oxidation stability and adhesion to the substrates but also has little effect on transparency contrary to typical passivation films. Besides, the electrochromic behaviors of the obtained AgNW/TPPA hybrid electrode demonstrated obvious multicolor appearance changes during their two oxidation stages. Finally, the AgNW/TPPA hybrid was fabricated as an electrochromic device (ECD) according to the ambipolar conduction behavior. The fabricated ECDs were also used in cyclic and differential pulse voltammetry techniques at a wide-range applied potential for continuous 300 switching cycles, which signifies that our proposed method has long-term operational stability. Thus, our fabrication strategy platform should enable an improved pathway to the development of optoelectronic devices and offer considerable promise for addressing growing concerns of device stability.