Synthesis of Vapor-Grown Carbon Fibers Using Nanocrystalline Fe_(91)Zr_7B_2 Alloy as a Catalyst

摘要

The synthesis of vapor-grown carbon fibers (VGCFs) using the nanocrystalline Fe_(91)Zr_7B_2 alloy as a novel catalyst, and the growth process of these VGCFs, have been investigated. We selected the nanocrystalline Fe_(91)Zr_7B_2 alloy as a novel catalyst for VGCF synthesis. The nanocrystalline Fe_(91)Zr_7B_2 alloy with fine bcc-Fe grains (approx 20 nm) was prepared by a melt-spinning technique followed by annealing at 873K for 5 min. VGCFs with a width ranging from 50 to 300nm and a maximum length of about 6 #mu# m were successfully prepared, by using a nanocrystalline Fe_(91)Zr_7B_2 alloy annealed at 873 K under a 80 percent CO-20 percent H_2 mixture. From HREM observation, it was found that the catalyst particle was made of fine bcc-Fe grains, and the VGCF consisted of graphite platelets with the spacing 0.396nm, that were stacked in a direction parallel to the base of the catalyst particle and perpendicular to the fiber axis. The growth process of the VGCF using the nanocrystalline Fe_(91)Zr_7B_2 alloy can be described by two major stages, i.e., "the separation of catalyst particles" and "fiber growth."