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通过不同的Hummers法和重铬酸钠氧化法,以商业石墨为原料,合成出不同氧含量和官能团的氧化石墨.采用元素分析、FTIR、XPS、SEM和XRD对氧化石墨进行化学和结构表征.重铬酸钾氧化能得到一种氧含量低的氧化石墨,主要形成羟基和环氧基.Hummers法是更有效的一种氧化方法.使用NaNO3氧化2 h,得到的氧化石墨具有最高的氧含量(>40 wt%),形成C—O和C=O键.SEM和XRD结果表明,在这些条件中,Hummers法合成的氧化石墨的石墨层间距最大.因此,用相同的氧化方法,通过改变反应条件能调控氧化石墨的化学结构.“,”Graphite oxides with different oxygen contents and specifications were prepared from a commercial graphite by different versions of the Hummers method and by oxidation with sodium dichromate. The chemical and structural characteristics of the graph-ite oxides were studied by elemental analysis( EA) , Fourier-transform infrared spectroscopy( FT-IR) , X-ray photoelectron spectros-copy(XPS), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Dichromate oxidation provided a low oxygen fixation, mainly in the form of hydroxyl and epoxy groups. A much more efficient oxidation was achieved by using the Hummers method. The use of NaNO3 and a reaction time of 2 h led to the highest oxygen content in the graphite oxide, over 40 wt%, and ox-ygen was found to be single-and double-bonded to carbon. SEM and XRD observations showed a high spacing of the graphitic lay-ers under these conditions. These results prove that, even using the same oxidizing method, the chemical structure of graphite oxides can be tailored by changing reaction conditions.