Researchers in the United States, Italy, and France have invented transistors made from cotton fibers that could be woven into clothing capable of measuring pollutants, T-shirts that display information, and carpets that sense how many people are crossing them.
“We want to create a seamless interface between electronics and textiles,” says Juan Hinestroza, director of the Textiles Nanotechnology Laboratory at Cornell University, in Ithaca, N.Y.
To make a fiber conductive, the team coated each strand with gold nanoparticles and added a thin layer of a conductive polymer. They created an organic electrochemical transistor and an organic field-effect transistor by doping the conductive fibers with a semiconducting polymer.
Ref.: Giorgio Mattana et al., Organic electronics on natural cotton fibres, Organic Electronics, 2011 [doi: 10.1016/j.orgel.2011.09.001]
The idea of electronic yarns and textiles has appeared for quite some time, but their properties often do not meet practical expectations. In addition to chemical/mechanical durability and high electrical conductivity, important materials qualifications include weavablity, wearability, light weight, and “smart” functionalities. Here we demonstrate a simple process of transforming general commodity cotton threads into intelligent e-textiles using a polyelectrolyte-based coating with carbon nanotubes (CNTs). Efficient charge transport through the network of nanotubes (20 Ω/cm) and the possibility to engineer tunneling junctions make them promising materials for many high-knowledge-content garments. Along with integrated humidity sensing, we demonstrate that CNT−cotton threads can be used to detect albumin, the key protein of blood, with high sensitivity and selectivity. Notwithstanding future challenges, these proof-of-concept demonstrations provide a direct pathway for the application of these materials as wearable biomonitoring and telemedicine sensors, which are simple, sensitive, selective, and versatile.
Ref : http://pubs.acs.org/doi/full/10.1021/nl801495p