Daejeon, KOREA - The researchers, from the Electronics and Telecommunications Research Institute and Konkuk University in the Republic of Korea, coated cotton and polyester yarn with a nanoglue called bovine serum albumin (BSA). The yarns were then wrapped in graphene oxide sheets.
Graphene is an incredibly strong one-atom-thick layer of carbon, and is known for its excellent conductive properties of heat and electricity. The graphene sheets stuck very well to the nanoglue - so much so that further testing showed the fabrics retained their electrical conducting properties after 1,000 consecutive cycles of bending and straightening and ten washing tests with various chemical detergents. Finally, the graphene oxide yarns were exposed to a chemical reduction process, which involves the gaining of electrons.
The reduced-graphene-oxide-coated materials were found to be particularly sensitive to detecting nitrogen dioxide, a pollutant gas commonly found in vehicle exhaust that also results from fossil fuel combustion. Prolonged exposure to nitrogen dioxide can be dangerous to human health, causing many respiratory-related illnesses. Exposure of these specially-treated fabrics to nitrogen dioxide led to a change in the electrical resistance of the reduced graphene oxide.
The fabrics were so sensitive that 30 minutes of exposure to 0.25 parts per million of nitrogen dioxide (just under five times above the acceptable standard set by the U.S. Environmental Protection Agency) elicited a response. The fabrics were three times as sensitive to nitrogen dioxide in air compared to another reduced graphene oxide sensor previously prepared on a flat material.
The new technology, according to the researchers, can be immediately adopted in related industries because the coating process is a simple one, making it suitable for mass production. It would allow outdoor wearers to receive relevant information about air quality. The materials could also be incorporated with air-purifying filters to act as "smart filters" that can both detect and filter harmful gas from air.
"This sensor can bring a significant change to our daily life since it was developed with flexible and widely used fibers, unlike the gas sensors invariably developed with the existing solid substrates," says Dr. Hyung-Kun Lee, who led this research initiative. The study was published on June 4 in the online edition of Scientific Reports, a journal from the publishers of Nature.
Image 1: The fiber sensor
Image 2: Dr Hyung-Kun Lee is measuring the fiber sensor
Image 3: Dr Hyung-Kun Lee is pointing the graph to monitor the experimental result
For more information, please contact
Dr Hyung-Kun Lee
E-mail: [email protected]
Tel: +82 42 860 5857
Established in 1976, ETRI is a non-profit Korean government-funded research organization that has been at the forefront of technological excellence for about 40 years. In the 1980s, ETRI developed TDX (Time Division Exchange) and 4M DRAM. In the 1990s, ETRI commercialized CDMA (Code Division Multiple Access) for the first time in the world. In the 2000s, ETRI developed Terrestrial DMB, WiBro, and 4G LTE Advanced, which became the foundation of mobile communications. Recently, as a global ICT leader, ETRI has been advancing communication and convergence by developing SAN (Ship Area Network) technology, Genie Talk (world class portable automatic interpretation; Korean-English/Japanese/Chinese), and automated valet parking technology. As of 2015, ETRI has about 2,000 employees where about 1,800 of them are researchers.
* Homepage : https://www.etri.re.kr/eng/main/main.etri
Press release distributed by ResearchSEA on behalf of ETRI.