title: Self-assembly of graphene on carbon nanotube surfaces.
abstract: The rolling up of a graphene sheet into a tube is a standard visualization tool for illustrating carbon nanotube (CNT) formation. However, the actual processes of rolling up graphene sheets into CNTs in laboratory syntheses have never been demonstrated. Here we report conformal growth of graphene by carbon self-assembly on single-wall and multi-wall CNTs using chemical vapor deposition (CVD) of methane without the presence of metal catalysts. The new graphene layers roll up into seamless coaxial cylinders encapsulating the existing CNTs, but their adhesion to the primary CNTs is weak due to the existence of lattice misorientation. Our study shows that graphene nucleation and growth by self-assembly of carbon on the inactive carbon basal plane of CNTs occurs by a new mechanism that is markedly different from epitaxial growth on metal surfaces, opening up the possibility of graphene growth on many other non-metal substrates by simple methane CVD.
authors.affiliation: College of Engineering and Department of Physics and Astronomy, University of Georgia, Athens, GA 30602, USA.
authors.forename: Kaiyuan
authors.initials: K
authors.lastname: Li
authors.forename: Gyula
authors.initials: G
authors.lastname: Eres
authors.forename: Jane
authors.initials: J
authors.lastname: Howe
authors.forename: Yen-Jun
authors.initials: YJ
authors.lastname: Chuang
authors.forename: Xufan
authors.initials: X
authors.lastname: Li
authors.forename: Zhanjun
authors.initials: Z
authors.lastname: Gu
authors.forename: Litong
authors.initials: L
authors.lastname: Zhang
authors.forename: Sishen
authors.initials: S
authors.lastname: Xie
authors.forename: Zhengwei
authors.initials: Z
authors.lastname: Pan
mesh_terms: D003460:Crystallization / Q000379:methods*; D006108:Graphite / Q000737:chemistry*; D008422:Materials Testing; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D037742:Nanotubes, Carbon; D006108:Graphite
references.citation: Nano Lett. 2009 Jan;9(1):30-5
references.pmid: 19046078
references.citation: Nature. 2009 Apr 16;458(7240):872-6
references.pmid: 19370030
references.citation: Nat Nanotechnol. 2008 Sep;3(9):563-8
references.pmid: 18772919
references.citation: Nat Nanotechnol. 2010 Aug;5(8):574-8
references.pmid: 20562870
references.citation: Nat Mater. 2011 Jun;10(6):424-8
references.pmid: 21478883
references.citation: Phys Rev Lett. 1992 Mar 9;68(10):1579-1581
references.pmid: 10045167
references.citation: Science. 2009 Jun 5;324(5932):1312-4
references.pmid: 19423775
references.citation: Science. 2004 Oct 22;306(5696):666-9
references.pmid: 15499015
references.citation: Nat Mater. 2008 May;7(5):406-11
references.pmid: 18391956
references.citation: Nano Lett. 2008 Feb;8(2):565-70
references.pmid: 18189442
references.citation: Nano Lett. 2006 Sep;6(9):1950-4
references.pmid: 16968006
references.citation: Nano Lett. 2005 Oct;5(10):1997-2000
references.pmid: 16218725
references.citation: ACS Nano. 2008 Oct 28;2(10):2113-20
references.pmid: 19206458
references.citation: Nature. 2011 Jun 22;474(7352):453-4
references.pmid: 21697938
references.citation: J Am Chem Soc. 2007 Mar 14;129(10):2730-1
references.pmid: 17300193
references.citation: Nature. 2009 Feb 5;457(7230):706-10
references.pmid: 19145232
references.citation: Nature. 2009 Apr 16;458(7240):877-80
references.pmid: 19370031