Coating turns fabrics into circuits

"We aim to build up the materials science so you can give us any garment you want, any fabric, any weave type, and turn it into a conductor,” said materials scientist Trisha Andrew.

“Such conducting textiles can then be built up into sophisticated electronics. One such application is to harvest body motion energy and convert it into electricity."

She claims that powering advanced fabrics that can monitor health data remotely are important to the military and increasingly valued by the healthcare industry.

Andrew's lab has made a wearable heart rate monitor with an off-the-shelf fitness bra to which they added eight monitoring electrodes.

According to the team, generating small electric currents through relative movement of layers is called triboelectric charging. Materials can become electrically charged as they create friction by moving against a different material.

"By sandwiching layers of differently materials between two conducting electrodes, a few microwatts of power can be generated when we move," Andrew explained.

The researchers used a vapour deposition method to coat fabrics with a conducting polymer, poly(3,4-ethylenedioxytiophene) also known as PEDOT, to make plain-woven, conducting fabrics that are resistant to stretching and wear and remain stable after washing and ironing.

The team reports results of testing electrical conductivity, fabric stability, chemical and mechanical stability of PEDOT films and textile parameter effects on conductivity for 14 fabrics, including five cottons with different weaves, linen and silk.

"This is a huge leap for consumer products, if you don't have to convince people to wear something different from what they are already wearing," Andrew added.