Using inexpensive materials, UC Berkeley engineers have fabricated foldable electronic switches and sensors directly onto paper, along with prototype generators, supercapacitors and other electronic devices.
They see many potential applications for the new, disposable paper electronics — for example, circuitry to detect heavy metal contamination could be “written” on paper to economically monitor toxins.
Research to develop paper electronics has accelerated in the last 10 years. Besides its availability and low cost, paper offers an intriguing potential: simply folding it could switch circuits on and off or otherwise change their activity — a kind of electronic origami.
But most efforts to fabricate electrodes onto paper with sufficient conductivity for practical use have employed expensive metals such as gold or silver as the conducting material.
This new technology solves that problem by using the inexpensive element molybdenum as the source of the conducting metal.
“Many people have been carrying out origami research, forming different architectures and different shapes to perform different functions,” says Liwei Lin, professor of mechanical engineering and senior author of a paper in the journal Advanced Materials reporting the versatile new technology. “We’ve now shown both the practicality of writing versatile conductive patterns on paper, and the durability of folding the electronic paper many hundreds of times for switching circuits on and off.”
He hopes the demonstrations can attract attention for use in capacitors and batteries.