【摘要】 以甲烷为碳源,硫酸亚铁为催化剂前驱体,通过化学气相沉积在石墨基板上制得毛线状炭纤维。扫描电子显微镜观察得知所制炭纤维具有毛线状结构,由许多直径更小的子纤维交叉合并而成。单束毛线状炭纤维的直径为4μm~8μm。高分辨透射电子显微镜显示构成纤维的碳层排列不平直,存在偏转角,有序排列的碳层被分割成许多有序微晶区域。进一步采用X射线衍射和激光拉曼光谱等分析手段对其微观结构进行表征,表明毛线状炭纤维中碳层排列有序度较高,石墨微晶尺寸较大(La≈5nm),层间距较小(d002=0.340nm)。推测毛线状炭纤维生长机理符合"吸附-扩散-析出"过程,形成毛线状结构主要由催化剂颗粒直径决定。更多还原

【Abstract】 Interwoven carbon nanofiber yarns were prepared from the catalytic pyrolysis of methane using ferrous sulfate and graphite as catalyst precursor and substrate respectively. They were characterized by SEM, HRTEM, XRD and Raman spectroscopy. Results indicated that the yarns had a diameter of 4-8 μm and consisted of interwoven carbon nanofibers. The catalyst particle was observed at the root of a yarn. The carbon nanofibers had a crystallite size (La) of about 5 nm and the d002 was 0.340 nm. The growth of the yarns complied with a adsorption-diffusion-precipitation mechanism and the diameter of yarn was determined by the size of the catalyst particle.更多还原