Table 1. Physical properties of GO dispersion.
Concentration (mg ml−1) | Volume fraction | Surface tension (mN m−1) | Contact angle (°) | Zero-shear viscosity (at 10−3 s−1) (Pa s) | Apparent viscosity (at 104 s−1) (Pa s) | Dewetting time (s) | Drying time (s) |
---|---|---|---|---|---|---|---|
0.1 | 0.005 | 71.9 | 81 | 0.00128 | 0.0016 | 0.012 | 40 |
5 | 0.27 | 68 | 70 | 0.0094 | 0.002 | 0.151 | 40 |
10 | 0.55 | 66 | 67 | 0.8 | 0.0041 | 15 | 40 |
40 | 2.22 | 49 | 49 | 66 | 0.0164 | 4313 | 40 |
Physical properties of a typical isotropic (0.1 mg ml−1), onset of bi-phasic (5 mg ml−1), bi-phasic (10 mg ml−1) and fully nematic (40 mg ml−1) colloidal dispersions of graphene oxide (GO) demonstrating a decrease in surface tension and contact angle which promotes wetting of the fluid on the porous substrate and an increase in dewetting time compared with drying time.