Premium
Carbon Nanotube Bags: Catalytic Formation, Physical Properties, Two‐Dimensional Alignment and Geometric Structuring of Densely Filled Carbon Tubes
Author(s) -
Schneider Jörg J.,
Engstler Jörg,
Franzka Steffen,
Hofmann Kathrin,
Albert Barbara,
Ensling Jürgen,
Gütlich Philipp,
Hildebrandt Peter,
Döpner Susanne,
Pfleging Wilhelm,
Günther Bernd,
Müller Günter
Publication year - 2001
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/1521-3765(20010702)7:13<2888::aid-chem2888>3.0.co;2-h
Subject(s) - structuring , carbon nanotube , catalysis , carbon fibers , materials science , geometric shape , chemical engineering , nanotechnology , composite material , chemistry , geometry , mathematics , engineering , business , organic chemistry , composite number , finance
The catalytic CVD synthesis, using propyne as carbon precursor and Fe(NO 3 ) 3 as catalyst precursor inside porous alumina, gives carbon nanotube (CNT) bags in a well‐arranged two‐dimensional order. The tubes have the morphology of bags or fibers, since they are completely filled with smaller helicoidal CNTs. This morphology has so far not been reported for CNTs. Owing to the dense filling of the outer mother CNTs with small helicoidal CNTs, the resulting CNT fibers appear to be stiff and show no sign of inflation, as sometimes observed with hollow CNTs. The fiber morphology was observed by raster electron microscopy (REM), transmission electron microscopy (TEM), and atomic force microscopy (AFM). The carbon material is graphitic as deduced from spectroscopic studies (X‐ray diffraction, Raman and electron energy‐loss spectroscopy (EELS)). From Mössbauer studies, the presence of two different oxidation states (Fe 0 and Fe III ) of the catalyst is proven. Geometric structuring of the template by two different methods has been studied. Inkjet catalyst printing shows that the tubes can be arranged in defined areas by a simple and easily applied technique. Laser‐structuring creates grooves of nanotube fibers embedded in the alumina host. This allows the formation of defined architectures in the μm range. Results on hydrogen absorption and field emission properties of the CNT fibers are reported.