Films of bamboo-like carbon nanotubes (BCNTs) were grown directly on copper substrates by sulfur-assisted hot filament chemical vapor deposition (HFCVD). The effects of substrate temperature and growth time over the BCNT structure were investigated. The films were characterized by scanning electron microscopy (SEM), Raman spectroscopy (RS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and electron field emission (EFE) studies. SEM and Raman characterization indicate a transition from the growth of microcrystalline diamond to the growth of a dense entangled network of carbon nanotubes or fibers as the substrate temperature is increased from 400 to900°Cthat is accounted for by the base growth model. TEM images show that the nanotubes have regular arrays of nanocavities. These BCNTs show good electron field emission properties as other carbon films.

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Films of bamboo-like carbon nanotubes ͑BCNTs͒ were grown directly on Cu substrates by hot filament chemical vapor deposition requiring no catalysts for growth. This is an efficient technique that yields a large density of active sites on the battery electrode. The thin films were characterized by scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The electrochemical properties of these BCNTs were studied by cyclic voltammetry ͑CV͒ and charge-discharge measurements.CV results indicate the formation of a solid electrolyte interface. The initial discharge capacity was found to be 880 Ah cm −2 m −1 , which is greater than the volumetric theoretical capacity of graphite, i.e., 84 Ah cm −2 m −1 . The reversible capacity remains at 205 Ah cm −2 m −1 after ten cycles. The nanocavities of the BCNTs appear to have a significant role in the large capacity for reversible Li insertion.

A dual stage process of depositing bamboo-like carbon nanotubes (BCNTs) by hot filament chemical vapor deposition (HFCVD) and coating Si using Radio frequency sputtering (RFS) technique. The films were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and electron field emission studies (EFE). SEM results suggest a dense network of homogeneous silicon-coated BCNTs. From the comprehensive analysis of the results provided by these techniques emerges the picture of Si encapsulated BCNTs.

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