剥离型高岭石纳米片的制备及其表征

Preparation and characterization of exfoliated kaolinite nanosheets

以高岭石原矿为起始原料,将其超声粉碎预处理后,采用醋酸钾预插层-甲酰胺剥离的两步法制备出了剥离型高岭石纳米片。利用动态光粒径测量仪、X射线衍射(XRD)、红外光谱(FTIR)、热重分析(TG)、扫描电子显微镜(SSEM)和透射电子显微镜((TEM)表征处理前后的高岭石结构与形貌的变化。相应的结果表明:经醋酸钾插层后,高岭石的层间距由d_(001)=0.706nm增大到d_(001)=1.42nm;以该高岭石/醋酸钾插层复合物为中间体,经甲酰胺与其二次作用后,高岭石层间距得到了充分的膨胀,层间作用力进一步削弱,最终获得了分散状态良好、层结构剥离型的高岭石硅酸盐纳米片。

Nanosheets material, near single-layer silicate structure was prepared from the raw kaolinite by a two- step method,which involved potassium acetate intercalation through grinding and formamide exfoliation through hot solution swelling successively. Dynamic light meter, XRD, FTIR,TG, SEM and TEM technologies were used to characterize the microstructure and morphology of kaolinite before and after exfoliation. The results showed that the basal spacing of the kaolinite increased from dco1 = 0. 706nm to d001 = 1.42nm after first intercalation with potassium acetate. The followed intercalation and swell of formamide further expanded the layer space of kaolinite and broke the hydrogen bonds between the silicate layers accordingly. Thus resulting in the exfoliation of the kaolinite layers and obtained the nanosheets material.