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

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.