Montmorillonite-carbon nanocomposites with nanosheet and nanotube structure: Preparation, characterization and structure evolution

In this study, the preparation of montmorillonite (Mt)-polyvinyl alcohol (PVA) nanocomposites (MtPVAN), and the formation of corresponding Mt carbon nanocomposites with nanosheet and nanotube structures were investigated. MtPVAN was prepared by solution intercalation combined with the dispersion method of ultrasonic radiation (UR) and mechanical stirring (MS). XRD analysis showed that the MtPVAN with d001 at 2.16 nm were successfully obtained with optimum mass ratio of 1:1.5 (Mt:PVA) and solid content of 10%. Then, the Mt-carbon, nanocomposites (d001 = 1.56 nm) with sandwich structure was prepared by carbonizing MtPVAN at 400 °C in nitrogen atmosphere for 3 h; and Mt-carbon nanosheets or nanotubes with carbon content of 5.10% was obtained by exfoliating the sandwich-like Mt-carbon nanocomposites with further airflow pulverization process. The average diameter and the thickness of the Mt-carbon nanosheets was about 2 μm and 10 nm, respectively; while the diameter of the nanotubes was 7–80 nm. The mechanism of the formation and the structure evolution of the Mt-carbon nanocomposites were also discussed.