The water contact angles of carbon monoliths are in the range of 108.6–130.0, increasing with the rising pyrolysis temperature (Fig. 6a). These differences in the wettability of carbon monoliths pyrolyzed at different temperatures can also be explained by FT-IR spectroscopy analysis (Fig. 6b). The FT-IR spectrum of C-350 sample shows several peaks of hydrophilic functional groups, such as C@O, CAO, and AOH, while C-600 sample reveals relatively weak hydrophilic peaks. For C-1000 sample, no functional groups are observed. As a result, C-1000 sample has the largestwater contact angle, whichmeans the highest hydrophobicity.