Jan 24, 2019
(Nanowerk News) Imagine folding up a paper-thin computer tablet like a newspaper. Such flexible electronics are moving closer to reality, according to a review in the journal Science and Technology of Advanced Materials ("Development and applications of transparent conductive nanocellulose paper").
Paper that is transparent and conducts electricity could have diverse applications, including foldable computers, transparent touch screens and even digital camouflage clothing. “With widespread and intensive efforts, low-cost and lightweight ‘green’ electronics fabricated on transparent nanopaper substrate will provide new technologies impacting our daily life,” state the review paper authors from Nanyang Technological University in Singapore.
Cellulose, the building block of paper taken from plants, is an exciting alternative to the plastic, glass and silicon that currently make up most electronic devices, including computers and mobile phones. Cellulose is renewable, biodegradable, strong and lightweight. For the past 30 years, scientists have considered ways to combine the smallest plant fibres, called ‘nanocellulose’, with electronics.
Portable solar cells based on foldable, lightweight, transparent, conductive cellulose nanofibre paper. (Image: CC-BY Macmillan Publishers Ltd)
For example, researchers at Nanyang Technological University have made nanopaper out of nanocellulose and silver nanowires. It still conducts electricity after being folded in half 500 times. Some nanopapers have reached 90% transparency, while others are in the 80% range similar to plastic.
But, better than plastic, nanopapers degrade quickly. After metal electrodes are removed, nanopaper can be buried in soil and will fully degrade within a month. However, this benefit is also a challenge: researchers are working on ways to prevent premature degradation. If they can solve this as well as bring down production costs, electronics could soon be built from plants.
![Portable solar cells based on foldable, lightweight, transparent, conductive cellulose nanofibre paper](https://www.nanowerk.com/nanotechnology-news2/id51972.jpg)