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Catalytic methods for the production of carbon nanotubules have been developed based on the decomposition of acetylene on well-dispersed metal particles strongly adsorbed on a support. Cobalt on silica was found to be the best catalyst—support combination for the production of graphitic tubules. The method for the catalyst preparation and the reaction conditions were optimized. Straight and coiled carbon tubules were obtained with inner and outer diameter of 3–7 and 15–20 nm, respectively, and up to 300 μm in length. These nanotubules were not coated by amorphous carbon. Traces of amorphous carbon could be removed by hydrogen. High resolution electron microscopy images and electron diffraction patterns of the straight nanotubules were similar to those obtained by the arc-discharge method. Coiled nanotubules were revealed by TEM to be regular polygonized helices where the bends are caused …