Growth of carbon nanotubes with metal-loading mesoporous molecular sieves catalysts

Chemical vapor deposition (CVD) was employed to catalytically synthesize carbon nanotubes (CNTs) with Fe- or Fe/Co-loading M41S (MCM-41 or MCM-48) as catalysts and benzene as precursor at 650°C. The experimental results indicated that the frameworks of the M41S host materials did not collapse after the synthesis process and well-graphitized curved CNTs ranging from 10 to 45nm in diameter could be formed out of the pores of the M41S materials. The maximum yield of CNTs per hour was greater than 200% the weight of the catalyst. Quite a few helix-shaped CNTs were obtained with the structures clearly demonstrated by high-resolution electron microscopy. The good thermal stability and high productivity observed in this study suggested that the mesoporous molecular sieves could be a kind of promising supports for catalytically synthesizing CNTs.