Carbon nanotubes are used in applications such as energy storages, electronic devices. For these applications, direct assembly of the well aligned and densely packed CNTs (VACNTs) on electrically conducting substrates is of interest. In this paper, we report a direct growth of the VACNTs on several substrates by using hot-filament chemical vapor deposition (hot-filament CVD) and a catalytic buffer-layer structure. The buffer layer was the Aluminum (Al) thin film used together with iron (Fe) as the catalyst. It was found that the underneath layer (Al) was critical for obtaining the VACNT forests with high purity and good contact. The as-fabricated VACNT/support-material structures are object to test field electron emission properties. Testing results of the VACNT samples demonstrated promising field emission characteristics in term of high emitting currents.

We herein introduce a new approach to synthesize MoO2/graphene composites via plasma-enhanced electrochemical exfoliation process. Our samples were prepared by electrifying graphite rods in (NH4)2Mo7O24 solution under a DC voltage of 70V. By controlling the experimental parameters such as the initial ratio of [Mo7O24]2– precursor, the current and time, we can modify the size and the size distribution of MoO2 nanoparticles on graphene sheets. The composites were characterized with Scanning Electron Microscopy, Transmission Electron Microscopy, X-ray Diffraction and Raman Spectroscopy.