GO aggregation and sedimentation kinetics in NaCl and CaCl 2 solutions. First, 500 mg of GO was sonicated (100 W, 40 kHz, 25 °C, 4 h) in 500 mL of ultrapure water. ... 2007), the measured GO layer thickness (1.5 ± 0.6 nm, Fig. S2A) reveals the dispersed GO was in single or double layers, and a few wrinkles and folds on the GO sheets were ...Web