石墨纤维表面与孔隙的结构表征及分形性质分析

为了研究和分析石墨纤维表面与孔隙的结构和分形性质,采用场发射扫描电子显微镜、电感耦合等离子体发射光谱仪、全自动物理吸附分析仪对其进行测试与表征.研究结果表明:石墨纤维以圆柱状存在,直径约为12～18 μm,表面较光滑,缺陷较少,有利于气体吸附;石墨纤维碳的质量分数约为95.86 %,还含有少量的N、H、O、S和微量的Ca、Fe、Mg、Si、Al等元素,生产过程中留下的孔道不多;石墨纤维的比表面积较大,其微孔体积占总孔体积的97.98 %,平均孔径在微孔区域,且孔径分布较窄,包含大量0.84 nm左右和少量1.21 nm左右的微孔,较丰富的微孔结构使其具有良好的吸附性能;石墨纤维的表面与孔隙具有较好的分形特性,分形维数分别为2.11和2.99,是一种有工业前景的吸附材料.

On characterization of structure and analysis of fractal nature of surface and pore of graphite fibers

Aiming to study and analyze structure and fractal nature of surface and pore of graphite fibers,they were tested and explored by applying field emission scanning electron microscope,inductively coupled plasma-atomic emission spectrometer,and automatic physical adsorption analyzer.The results show that graphite fibers are cylindrical,diameter about 12—18 μm,relatively smooth surface,and fewer defects,which is conducive to gas adsorption.The carbon content of graphite fibers is about 95.86 %,containing a small amount of N,H,O,S and trace amount of Ca,Fe,Mg,Si,Al elements and so on,which the pores left in the production process is not much.Graphite fibers are of larger specific surface area,in which the micropore volume is 97.98 % of the total pore volume with the average pore size in the micropore region.In addition,pore size distributions are relatively narrow,and contain a large number of micropore about 0.84 nm and a small amount of microporous about 1.21 nm,which presents richer micropore structures so that it is equipped with good adsorption properties.surface and pore of graphite fibers have good fractal characteristics,whose fractal dimension are 2.11 and 2.99,respectively,and which are adsorbent materials with excellent industrial prospects.