In situ observation of carbon-nanopillar tubulization caused by liquidlike iron particles -: art. no. 215702

The tubulization process of amorphous carbon nanopillars was observed in situ by transmission electron microscopy. Amorphous carbon nanopillars were transformed into graphitic tubules by annealing at 650-900 degreesC in the presence of iron nanoparticles. A molten catalyst nanoparticle penetrated an amorphous carbon nanopillar, dissolving it, and leaving a graphite track behind. An iron nanoparticle moved with its shape changing like an earthworm. We concluded that the tubulization mechanism is a solid-(quasiliquid)-solid mechanism where the carbon phase transformation is a kind of liquid phase graphitization of amorphous carbon catalyzed by liquefied metal-carbon alloy nanoparticles.