Electrically Conductive Textiles Enabled by Silver Nanowires
There has been steep growth in wearable devices over the past 5 years and the ability to seamlessly integrate these devices into clothing is an exciting next step. So called e-textiles or smart textiles are of immense interest in other textile applications as well such as window blinds and tents. One crucial component of achieving e-textiles is the ability of a textile to be electrically conductive for signal and power transfer. Commercially available conductive fabric typically involves metal plating, but these can degrade with bending. Another issue with these plated coatings is that the deposition process is expensive and the process requires specialized, expensive equipment. Overall the weight of these textiles is also greater because of the high quantity of metal used. Recent alternative coatings such as polymers and carbon nanotubes have issues with low lifetimes and poor conductivity, respectively.
Through my research, these problems are addressed by coating fabrics with networks of solution-processed silver nanowires. These silver nanowire coatings are conductive and mechanically flexible. Sheet resistances as low as 0.5 ?/square were achieved. Several deposition techniques were explored including dip coating, brush coating, and transfer printing. Of these, transfer printing uses the least amount of silver and is therefore lowest in cost. Furthermore, compared to metal plating or the weaving of conductive thread, its deposition is simple and inexpensive. Overall, we demonstrate an industrially-compatible, printable coating that can impart conductivity to a wide range of fabrics.