TY - JOUR
T1 - High-yield growth and morphology control of aligned carbon nanotubes on ceramic fibers for multifunctional enhancement of structural composites
AU - Yamamoto, Namiko
AU - John Hart, A.
AU - Garcia, Enrique J.
AU - Wicks, Sunny S.
AU - Duong, Hai M.
AU - Slocum, Alexander H.
AU - Wardle, Brian L.
N1 - Funding Information:
This work was supported by Airbus S.A.S., Boeing, Embraer, Lockheed Martin, Saab AB, and Spirit AeroSystems, Textron Inc., Composite Systems Technology, and TohoTenax through MIT’s Nano-Engineered Composite Structures Consortium. Additional support was provided by MIT’s Karl Chang (1965) Innovation Fund. The authors gratefully thank Roberto Guzman de Villoria, Stephen A. Steiner III, John Kane, and other members of the Technology Laboratory for Advanced Materials and Structures at MIT for valuable discussions and technical support. Namiko Yamamoto acknowledges the Linda and Richard (1958) Hardy Fellowship; John Hart acknowledges a Fannie and John Hertz Foundation Graduate Fellowship; Enrique Garcia thanks the La Caixa Foundation; and Sunny Wicks appreciates funding from MIT’s Paul E. Gray (1954) Undergraduate Research Opportunity Fund.
Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.
PY - 2009/3
Y1 - 2009/3
N2 - We present an in-depth study of CNT growth on commercially-available woven alumina fibers, and achieve uniform growth of dense aligned CNTs on commercially-available cloths up to 5 × 10 cm in area. By systematically varying the catalyst concentration, catalyst pre-treatment time, and sample position within the tube furnace, we isolate key factors governing CNT morphology on fiber surfaces and classify these morphologies as related to the processing conditions. Synthesis employs a low-cost salt-based catalyst solution and atmospheric pressure thermal CVD, which are highly attractive approaches for commercial-scale processing. The catalyst solution concentration determines the uniformity and density of catalyst on the fibers, H2 exposure mediates formation of catalyst clusters, and thermal decomposition of the reactant mixture activates the catalyst particles to achieve uniform aligned growth. Under conditions for aligned CNT growth, uniform radially-aligned coatings are achieved with shorter CNT length, and these split into "mohawks" as the CNT length increases. Radially-aligned growth for 5 min adds a typical CNT mass fraction of 3.8% to the initial sample mass, and a uniform morphology exists throughout the weave. Composites prepared by standard layup techniques using these CNT "fuzzy" alumina fibers are attractive as integral armor layers having enhanced ballistic and impact performance, and serve as a model system for later implementation of this technology using carbon fibers.
AB - We present an in-depth study of CNT growth on commercially-available woven alumina fibers, and achieve uniform growth of dense aligned CNTs on commercially-available cloths up to 5 × 10 cm in area. By systematically varying the catalyst concentration, catalyst pre-treatment time, and sample position within the tube furnace, we isolate key factors governing CNT morphology on fiber surfaces and classify these morphologies as related to the processing conditions. Synthesis employs a low-cost salt-based catalyst solution and atmospheric pressure thermal CVD, which are highly attractive approaches for commercial-scale processing. The catalyst solution concentration determines the uniformity and density of catalyst on the fibers, H2 exposure mediates formation of catalyst clusters, and thermal decomposition of the reactant mixture activates the catalyst particles to achieve uniform aligned growth. Under conditions for aligned CNT growth, uniform radially-aligned coatings are achieved with shorter CNT length, and these split into "mohawks" as the CNT length increases. Radially-aligned growth for 5 min adds a typical CNT mass fraction of 3.8% to the initial sample mass, and a uniform morphology exists throughout the weave. Composites prepared by standard layup techniques using these CNT "fuzzy" alumina fibers are attractive as integral armor layers having enhanced ballistic and impact performance, and serve as a model system for later implementation of this technology using carbon fibers.
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U2 - 10.1016/j.carbon.2008.10.030
DO - 10.1016/j.carbon.2008.10.030
M3 - Article
AN - SCOPUS:58549107785
SN - 0008-6223
VL - 47
SP - 551
EP - 560
JO - Carbon
JF - Carbon
IS - 3
ER -