The quality of the exfoliation by ultrasonic waves is evident in the comparison

with chemically delaminated BN produced by the modified Hummers method [36]. As seen in the picture from the AFM microscope (see Figure 8), chemical delamination provided mostly 10-nm-thick see more particles of h-BN. Figure 4 AFM images and analysis of exfoliated MoS 2 formed via (a) dimethylformamide and (b) an alkaline solution of potassium manganate. Figure 5 AFM images and analysis of exfoliated WS 2 in (a) dimethylformamide and (b) CX-6258 an alkaline solution of potassium manganate. Figure 6 AFM image and analysis of exfoliated h-BN. Figure 7 AFM image and analysis of exfoliated h-BCN. Figure 8 AFM image and analysis of chemically exfoliated h-BN. The AFM image of exfoliated g-C3N4 SYN-117 in ethylene glycol is shown in Figure 9. From the image analysis, it is clear that the exfoliated sample formed particles of 60 to 80 nm in size with heights of approximately 1.6 nm. A high-resolution AFM image is presented in Figure 10. Cross-sectional analysis showed that the exfoliated g-C3N4 sheet has a thickness of approximately 0.1 nm and the sheet has a size of approximately 80 × 100 nm. These results correspond with the results from SAED for bilayer particles. Figure 9 AFM images and analysis of exfoliated g-C 3 N 4 . Figure 10 High-resolution AFM image and analysis of exfoliated g-C 3 N 4 . Zhi et al. [49] presented

exfoliation of bulk h-BN in dimethylformamide by sonication for 10 h with subsequent centrifugation to remove residual large-sized BN particles. Approximately 0.5 to 1 mg of h-BN nanosheets could be routinely obtained from 1 g of the bulk h-BN powder; this corresponds to a yield of exfoliation of approximately 1%. The liquid exfoliation of layered materials [50, 51] provided similar yields. All the aforementioned

cited exfoliation methods improve yields by countless repetition PtdIns(3,4)P2 of exfoliation with the necessary intermediate operations (centrifugation) that isolate exfoliated products from the initial suspension. The resulting product is a diluted dispersion of the nanosheets in a suitable solvent. Here, the reported method using the high-power ultrasound produced a concentrated colloidal dispersion of nanosheets by one-step sonication; the product possesses a relatively homogeneous distribution of the few- or monolayers, as seen in the AFM images. By this method, large quantities of the colloidal dispersion of nanosheets are readily available as a precursor (for example, for the preparation of composites) and can be produced in a short time. Using an alkaline medium to prepare exfoliated IAGs could be an important shift in the preparation of these materials. Using alkaline solutions for ultrasonic preparation could exclude hydrophobic organic solvents and consequently contamination by organic residuals and undesired functionalization of the nanosheets.