In one aspect of the invention, a method for growth of carbon nanotubes includes providing a graphitic composite, decorating the graphitic composite with metal nanostructures to form graphene-contained powders, and heating the graphene-contained powders at a target temperature to form the carbon nanotubes in an argon/hydrogen environment that is devoid of a hydrocarbon source. In one embodiment, the target temperature can be as low as about 150.degree. C. (.+-.5.degree. C.).
STATEMENT AS TO RIGHTS UNDER FEDERALLY-SPONSORED RESEARCH
 This invention was made with government support under EPS-1003970 awarded by the National Science Foundation VICTER Project, and under DE-FG36-06G086072 awarded by the Department of Energy. The government has certain rights in the invention.