title: Preferential growth of short aligned, metallic-rich single-walled carbon nanotubes from perpendicular layered double hydroxide film.
abstract: Direct bulk growth of single-walled carbon nanotubes (SWCNTs) with required properties, such as diameter, length, and chirality, is the first step to realize their advanced applications in electrical and optical devices, transparent conductive films, and high-performance field-effect transistors. Preferential growth of short aligned, metallic-rich SWCNTs is a great challenge to the carbon nanotube community. We report the bulk preferential growth of short aligned SWCNTs from perpendicular Mo-containing FeMgAl layered double hydroxide (LDH) film by a facile thermal chemical vapor deposition with CH(4) as carbon source. The growth of the short aligned SWCNTs showed a decreased growth velocity with an initial value of 1.9 nm s(-1). Such a low growth velocity made it possible to get aligned SWCNTs shorter than 1 μm with a growth duration less than 15 min. Raman spectra with different excitation wavelengths indicated that the as-grown short aligned SWCNTs showed high selectivity of metallic SWCNTs. Various kinds of materials, such as mica, quartz, Cu foil, and carbon fiber, can serve as the substrates for the growth of perpendicular FeMoMgAl LDH films and also the growth of the short aligned SWCNTs subsequently. These findings highlight the easy route for bulk preferential growth of aligned metallic-rich SWCNTs with well defined length for further bulk characterization and applications.
authors.affiliation: Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Meng-Qiang
authors.initials: MQ
authors.lastname: Zhao
authors.forename: Gui-Li
authors.initials: GL
authors.lastname: Tian
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Jia-Qi
authors.initials: JQ
authors.lastname: Huang
authors.forename: Jing-Qi
authors.initials: JQ
authors.lastname: Nie
authors.forename: Fei
authors.initials: F
authors.lastname: Wei
mesh_terms: D000535:Aluminum / Q000737:chemistry; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis / Q000737:chemistry; D003460:Crystallization; D006878:Hydroxides / Q000737:chemistry*; D007501:Iron / Q000737:chemistry; D008274:Magnesium / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D008954:Models, Biological; D008982:Molybdenum / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009994:Osmolar Concentration
chemical_list: D020099:Coated Materials, Biocompatible; D006878:Hydroxides; D008670:Metals; D037742:Nanotubes, Carbon; D008982:Molybdenum; C031356:hydroxide ion; D000535:Aluminum; D007501:Iron; D008274:Magnesium