Browsing by Author "Wang, Xuan"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Carbon nanotube woven textile photodetector
    (American Physical Society, 2018) Zubair, Ahmed; Wang, Xuan; Mirri, Francesca; Tsentalovich, Dmitri E.; Fujimura, Naoki; Suzuki, Daichi; Soundarapandian, Karuppasamy P.; Kawano, Yukio; Pasquali, Matteo; Kono, Junichiro
    The increasing interest in mobile and wearable technology demands the enhancement of functionality of clothing through incorporation of sophisticated architectures of multifunctional materials. Flexible electronic and photonic devices based on organic materials have made impressive progress over the past decade, but higher performance, simpler fabrication, and most importantly, compatibility with woven technology are desired. Here we report on the development of a weaved, substrateless, and polarization-sensitive photodetector based on doping-engineered fibers of highly aligned carbon nanotubes. This room-temperature-operating, self-powered detector responds to radiation in an ultrabroad spectral range, from the ultraviolet to the terahertz, through the photothermoelectric effect, with a low noise-equivalent power (a few nW/Hz1/2) throughout the range and with a ZT-factor value that is twice as large as that of previously reported carbon nanotube-based photothermoelectric photodetectors. Particularly, we fabricated a ∼1-m-long device consisting of tens of p+−p− junctions and weaved it into a shirt. This device demonstrated a collective photoresponse of the series-connected junctions under global illumination. The performance of the device did not show any sign of deterioration through 200 bending tests with a bending radius smaller than 100 μm as well as standard washing and ironing cycles. This unconventional photodetector will find applications in wearable technology that require detection of electromagnetic radiation.
  • Thumbnail Image
    Item
    High-Ampacity Power Cables of Tightly-Packed and Aligned Carbon Nanotubes
    (Wiley, 2014) Wang, Xuan; Behabtu, Natnael; Young, Colin C.; Tsentalovich, Dmitri E.; Pasquali, Matteo; Kono, Junichiro; Richard E. Smalley Institute for Nanoscale Science and Technology
    The current-carrying capacity (CCC), or ampacity, of highly-conductive, light, and strong carbon nanotube (CNT) fibers is characterized by measuring their failure current density (FCD) and continuous current rating (CCR) values. It is shown, both experimentally and theoretically, that the CCC of these fibers is determined by the balance between current-induced Joule heating and heat exchange with the surroundings. The measured FCD values of the fibers range from 107 to 109 A m−2 and are generally higher than the previously reported values for aligned buckypapers, carbon fibers, and CNT fibers. To the authors’ knowledge, this is the first time the CCR for a CNT fiber has been reported. The specific CCC value (i.e., normalized by the linear mass density) of these CNT fibers are demonstrated to be higher than those of copper.
  • Thumbnail Image
    Item
    Strong, Light, Multifunctional Fibers of Carbon Nanotubes with Ultrahigh Conductivity
    (AAAS, 2013) Behabtu, Natnael; Young, Colin C.; Tsentalovich, Dmitri E.; Kleinerman, Olga; Wang, Xuan; Ma, Anson W.K.; Bengio, E. Amram; ter Waarbeek, Ron F.; de Jong, Jorrit J.; Hoogerwerf, Ron E.; Fairchild, Steven B.; Ferguson, John B.; Maruyama, Benji; Kono, Junichiro; Talmon, Yeshayahu; Cohen, Yachin; Otto, Marcin J.; Pasquali, Matteo; Richard E. Smalley Institute for Nanoscale Science and Technology
    Broader applications of carbon nanotubes to real-world problems have largely gone unfulfilled because of difficult material synthesis and laborious processing. We report high-performance multifunctional carbon nanotube (CNT) fibers that combine the specific strength, stiffness, and thermal conductivity of carbon fibers with the specific electrical conductivity of metals. These fibers consist of bulk-grown CNTs and are produced by high-throughput wet spinning, the same process used to produce high-performance industrial fibers. These scalable CNT fibers are positioned for high-value applications, such as aerospace electronics and field emission, and can evolve into engineered materials with broad long-term impact, from consumer electronics to long-range power transmission.