Cement Pastes and Mortars Containing Nitrogen-Doped and Oxygen-Functionalized Multiwalled Carbon Nanotubes

Figure 4

Methodology for the dispersion of carbon nanotubes. (a) SEM micrograph showing as-produced carbon nanotubes (bundles), which are introduced in a water tank. A pump is installed inside the water tank to supply the solution based on water + carbon nanotubes to the ultrasonic tip equipment. (b) Ultrasonic tip equipment connected to an ultrasonic processor operated at 20 kHz and 1500 Watts. (c), (d), and (e) TEM images showing the resulting dispersed carbon nanotubes.