Shape‐Controlled Growth of Carbon Nanostructures: Yield and Mechanism

Carbon nanostructures with precisely controlled shapes are difficult materials to synthesize. A facet‐selective‐catalytic process was thus proposed to synthesize polymer‐linked carbon nanostructures with different shapes, covering straight carbon nanofiber, carbon nano Y‐junction, carbon nano‐hexapus, and carbon nano‐octopus. A thermal chemical vapor deposition process was applied to grow these multi‐branched carbon nanostructures at temperatures lower than 350 °C. Cu nanoparticles were utilized as the catalyst and acetylene as the reaction gas. The growth of those multi‐branched nanostructures was realized through the selective growth of polymer‐like sheets on certain indexed facets of Cu catalyst. The vapor–facet–solid (VFS) mechanism, a new growth mode, has been proposed to interpret such a growth in the steps of formation, diffusion, and coupling of carbon‐containing oligomers, as well as their final precipitation to form nanostructures on the selective Cu facets.