{'fraction_non_alphanumeric': 0.04091456077015644, 'fraction_numerical': 0.007220216606498195, 'mean_word_length': 6.0508474576271185, 'pattern_counts': {'":': 0, '<': 1, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Diameter controlled growth of iron‐filled carbon nanotubes

We report the chemical vapor deposition of Fe‐filled carbon nanotubes (CNTs) from metallorganic precursors (ferrocene, cyclopentadienyliron dicarbonyl dimer) on oxidized silicon substrates precoated with single‐layered or multi‐layered catalyst films (Fe, Au/Fe or Au/Al/Fe). The performed experiments result in thin multi‐walled carbon nanotubes (<40 nm) with a narrow diameter distribution and containing up to several micrometer long single crystalline iron nanorods. Electron scanning microscopy shows that the CNTs grow vertically aligned to the substrate surface. Furthermore transmission electron microscopy (TEM) indicates nearly impurity free CNTs. These investigations are also complemented by X‐ray analysis. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)