For many years, researchers have been developing means of producing circuits using additive manufacturing techniques. Although this has been quite successful – allowing for cheap, precise, quick-to-produce electronics – the metal particles used to make these “inks” conductive are exacerbating the problem of electronic waste. This is particularly concerning given the likelihood that printed electronics will be largely used in cheap, disposable IOT sensors.
“There is an urgent need for materials that balance electronic performance, cost, and sustainability,” said Professor Gustav Nyström, head of Empa’s Cellulose and Wood Materials lab.
In order to develop an environmentally friendly ink, Nyström and his colleagues set the goal of making it metal-free, non-toxic, and biodegradable. Having practical applications in mind, they also aimed to ensure it was easily formable and stable to moisture and moderate heat.
They chose as their conductive material inexpensive...