With 62 million tonnes of electronic waste discarded worldwide in 2024 and less than 17 per cent recycled in the EU, the environmental case for rethinking the printed circuit board is stark. Engineers at the University of Glasgow's James Watt School of Engineering have developed a response: a growth and transfer additive manufacturing process that prints zinc-based circuits onto biodegradable surfaces such as paper and bioplastics, replacing the copper tracks of conventional boards.
The zinc tracks, just five microns wide, are electroplated onto a temporary carrier and then transferred to the biodegradable substrate. In testing, the circuits performed comparably to traditional boards in tactile sensors, LED counters and temperature sensors, and remained stable after more than a year in ambient conditions. At end of life, 99 per cent of the materials can be returned to the environment through soil composting or dissolved using household chemicals such as vinegar.
A life cycle assessment suggests the approach could cut global warming potential by 79 per cent and resource depletion by 90 per cent compared with conventional boards. The work, published in Communications Materials with Dr Jonathon Harwell as first author and Professor Jeff Kettle as corresponding author, sits within REACT, the Responsible Electronics and Circular Technology Centre led by Glasgow and backed by more than six million pounds of UKRI funding as one of five Green Economy Centres.