质子束轰击下MWCNTs无定形结构的转变

Amorphous structure transformation of MWCNTs irradiated by 70 keV protons

在室温下用70keV质子束多壁碳纳米管(MWCNTs),研究了多壁碳纳米管从石墨结构向无定形结构的转变过程。轰击后,MWCNTs外围的石墨结构变成均匀的无定形结构包覆着内部的石墨结构。增大照射量,这种无定形化的过程继续向MWCNTs内层推进,直至形成一个中空的无定形纳米线结构。质子束轰击引入的MWCNTs的结构转变,是从外层向内层逐步推进的石墨结构向无定形结构的转变过程。本文对这种结构演化的机理进行了讨论。

Amorphous structure transformation of multiwalled carbon nanotubes （MWCNTs） irradiated by 70 keV protons at room temperature was investigated. It was found that some of the proton-irradiated MWCNTs were covered with homogeneous amorphous structure with the inner tube walls in graphite structure. Moreover, the amorphous structure continuously proceeds and the graphite structure was reduced during the proton irradiation until the irradiated MWCNTs become amorphous nanowires with a hollow structure. The proton-induced structural transformation of MWCNTs was a unique graphite-to-amorphous structural transition from the outer walls to the inner walls of the irradiated MWCNTs. The structural evolutionary mechanism of proton-beam-irradiated MWCNTs has been discussed.