Directly Electroplated Metallization on Flexible Substrates Based on Silver Nanowire Conductive Composite for Wearable Electronics

Abstract

The metallization of flexible polymer surface is a necessary process to realize the electrical interconnection of insulating substrates, which is of great significance for the fabrication of flexible wearable electronics. Herein, a method for the fabrication of a metal/ polymer composite is presented on the basis of a silver nanowire (AgNW) conductive composite by direct copper electroplating. A precoating was first coated on the polyethylene terephthalate (PET) substrate to form the interspace structures on the surface. AgNWs could just be embedded into these interspace structures by the means of coating to obtain excellent adhesion. Furthermore, these interspace structures were filled with deposited copper atoms, thus contributing to a strong interlock between the plated copper layer and the substrate. The obtained Cu/PET composites were subjected to morphological and mechanical characterizations to analyze the peeling strength, crystalline structure, and surface morphology of the plated copper layer. Experimental results show that the plated copper layer is dense and consistent with a maximum peel strength of 11 N cm −1 . In addition, large scale of the Cu/PET (20 cm × 30 cm) composite with a thickness of 21 μm was fabricated by this method, and copper patterns were further fabricated using a conventional etching process. The fabricated copper patterns exhibit an outstanding electrical stability after 3000 times of a bending fatigue test, proving the excellent flexibility of the Cu/PET composite. In conclusion, this approach provides an insight into the design of metal/ polymer composites addressing a significant potential application in flexible printed circuit, electrode, and antenna for wearable electronics.

All-atmospheric fabrication of Ag–Cu core–shell nanowire transparent electrodes with Haacke figure of merit >600 × 10–3 Ω−1

“…Our nanowire TCE fabrication process focuses on performance and simplified processing. Though prior reports have demonstrated copper plating on silver nanowire seed layers 41 , 42 , the present work uniquely forms core–shell structures and targets TCE applications. The process leverages a recent development in direct metallization by Kiremitler et al who incorporated reactive silver ink into an electrospinning solution 31 .…”

Wet Film Leveling for Promoting the Uniformity and Conductivity of Silver Nanowire Transparent Electrode

“…As the base of flexible electronics, a silver nanowire (AgNW) transparent electrode has broad application prospects. − For practical application, the uniformity of the transparent electrode is important. To promote the uniformity of AgNW transparent electrode, researchers have developed many excellent strategies. − First, researchers improve the wettability between the ink and the substrate. , Specific methods include adjusting the surface tension of the ink and substrate by the following methods: ozone activation, corona treatment, binder coating, adding surfactant or low-surface-tension material, etc. − Second, the drying process is carefully controlled to relieve the problem of coffee ring and punctate film. − Third, the film-preparation technology (ink dosage, coating speed, etc.) is optimized. , Through these strategies, the uniformity of the AgNW transparent electrode is greatly improved.…”

Flexible Paper-Based Room-Temperature Acetone Sensors with Ultrafast Regeneration

“…In recent years, flexible and wearable electronic sensors have extensively attained much attention due to their potential applications in human–machine intelligence, − healthcare, − and smart cities . To achieve flexibility in sensors, polymer substrates like polyimide (PI), poly­(dimethylsiloxane) (PDMS), , and poly­(ethylene terephthalate) (PET) have been employed. However, these polymeric substrates are vulnerable to degradation, resulting in severe environmental issues.…”