Significant changes were verified in the materials morphology.
As can be seen in Fig. 3a, SEM image shows a slightly damaged and
uneven surface, which may be due to the release of volatile
materials during carbonization process. After activation process,
the image of ACb (Fig. 3b) shows a discontinuous surface, caused by
the dehydrating action of activating agent, which leads to the
porosity development [41].