New technique prints silver nanowires that stretch and flex

Researchers have developed a new technique that enables circuits to be printed on flexible, stretchable substrates using silver nanowires.

The advance from a group at North Carolina State University (NC State) is said to make it possible to integrate the material into an array of electronic devices.

Silver nanowires are flexible, stretchable and conductive. Consequently, they have attracted interest for use in prosthetic devices and wearable sensors but challenges exist.

Silver nanoparticles can be used to print circuits, but the nanoparticles produce circuits that are more brittle and less conductive than silver nanowires. Conventional techniques for printing circuits don’t work well with silver nanowires as the nanowires can clog the printing nozzles.

“Our approach uses electrohydrodynamic printing, which relies on electrostatic force to eject the ink from the nozzle and draw it to the appropriate site on the substrate,” said Jingyan Dong, co-corresponding author of a paper on the work and an associate professor in NC State’s Edward P. Fitts Department of Industrial & Systems Engineering. “This approach allows us to use a very wide nozzle – which prevents clogging – while retaining very fine printing resolution.”