Chemical Vapor Deposition Growth of Carbon Micro-Tubes

Carbon microtube (CMT) is a newly emerging morphological form of carbon fibril with micrometer scale diameter and thin graphitic walls. However, similar to the carbon nanotubes (CNT), CMTs grown via Chemical vapor deposition (CVD) method are in the form of membranes. Currently there is no feasible and reliable method to separate single CMT from the membrane without structure impairment. In this paper, we reported large scale cvd synthesis of readily separable CMTs. Instead of taking a membrane form, the synthesized CMTs were in a distinct fiber form which is easily separable. The diameter of CMTs ranged from 500 nanometers to about 2 micrometers with an average value of 1.7 micrometers, and the length was from several millimeters to around 1 cm. Attributing to their micro scale, the multi-layer tubular structure of CMTs was for the first time observed with scanning electron microscopy (SEM). The graphite structure of CMTs was verified with X-ray diffraction (XRD) and selected area electron diffraction (SAED). The separable status of CMTs facilitates their manipulation and opens a new way of manufacturing microelectronics and microdevices with single CMT.