PACK POINTS
Plug-in textiles
Imagine plugging a USB port into a sheet of paper and turning it into a tablet computer. It might be a stretch, but ideas like this have researchers at NC State examining the use of conductive nanocoatings on simple textiles — such as woven cotton or even a sheet of paper.
“Normally, conductive nanocoatings are applied to inorganic materials such as silicon. If we can find a way to apply them to textiles — cheap, flexible materials with a contorted surface texture — it would represent a cost-effective approach and framework for improving current and future types of electronic devices,” said Dr. Jesse Jur, assistant professor of textile engineering, chemistry and science, and lead author of a paper describing the research.
Using a technique called atomic layer deposition, coatings of inorganic materials, typically used in devices such as solar cells, sensors and microelectronics, were grown on the surface of textiles like woven cotton and nonwoven polypropylene — the same material that goes into reusable grocery store bags. The research, done in collaboration with Dr. Gregory Parsons, Alcoa Professor of Chemical and Biomolecular Engineering; post-doctoral researcher Christopher Oldham; and graduate student William Sweet, shows that common textile materials can be used for complex electronic devices.
As part of their study, the researchers created a new procedure to quantify effective electrical conductivity of conductive coatings on textile materials. The current standard of measuring conductivity uses a four-point probe that applies a current between two probes and senses a voltage between the other two probes. However, these probes were too small and would not give the most accurate reading for measurements on textiles.
In their paper, the researchers describe a new technique using larger probes that accurately measures the conductivity of the nanocoating. This new system gives researchers a better understanding of how to apply coatings on textiles to turn them into conductive devices.
“Research like this has potential health and monitoring applications since we could potentially create a uniform with cloth sensors embedded in the actual material that could track heart rate, body temperature, movement and more in real time,” Jur said.