摘要
Carbonaceous materials,such as graphite,carbon nanotubes(CNTs),and graphene,are in high demand for a broad range of applications,including batteries,capacitors,and composite materials.Studies on the transformation between diferent types of carbon,especially from abundant and low-cost carbon to high-end carbon allotropes,have received surging interest.Here,we report that,without a catalyst or an external carbon source,biomass-derived amorphous carbon and defective reduced graphene oxide(RGO)can be quickly transformed into CNTs in highly confned spaces by high temperature Joule heating.Combined with experimental measurements and molecular dynamics simulations,we propose that Joule heating induces a high local temperature at defect sites due to the corresponding high local resistance.Te resultant temperature gradient in amorphous carbon or RGO drives the migration of carbon atoms and promotes the growth of CNTs without using a catalyst or external carbon source.Our fndings on the growth of CNTs in confned spaces by fast high temperature Joule heating shed light on the controlled transition between diferent carbon allotropes,which can be extended to the growth of other high aspect ratio nanomaterials.
基金
The authors acknowledge the support of the Maryland NanoCenter and its AIMLab.
