A method for the direct growth of carbon nanotubes on macroscopic carbon substrates

A simple and general approach is reported for the direct growth of carbon nanotubes (CNTs) on macroscopic carbon substrates. Two typical geometries of biomass materials, cellulose fibers or rice husks, are chosen to act as the precursor of carbon substrates, and commercial polypropylene (PP) pellets are used as the carbon source of CNTs with the presence of Ni–Mo–Mg catalysts. This simple and general strategy was realized by a direct pyrolyzation of the PP blends containing biomass materials and Ni–Mo–Mg catalysts in a chemical vapor deposition device at 800 °C under nitrogen’s protection. The carbon products were characterized by various techniques such as X-ray diffractometer, transmission electron microscopy, scanning electron microscopy, Raman spectroscopy, and thermogravimetric analysis. Results show that the CNTs are successfully grown on the macroscopic carbon substrate derived from cellulose fibers or rice husks, whereas the addition of biomass materials as carbon precursors has to some extent an influence on the morphology of CNTs in the carbon products.