| 초록 |
In this study, water-dispersible porous g-C3N4 photocatalysts were prepared from bulk g-C3N4 by a chemical oxidation method and their photocatalytic activity was examined under visible-light irradiation. Bulk g-C3N4 was obtained from different C and N rich precursors such as dicyandiamide, melamine, urea, and thiourea in a muffle furnace at 550oC for 4 hours under air condition. Properties of bulk and porous g-C3N4 materials were characterized by FE-SEM, XRD, FT-IR, BET and UV–vis absorption. Porous g-C3N4 photocatalysts showed a higher photocatalytic degradation rate of methylene blue than bulk g-C3N4. Photocatalytic activities of porous g-C3N4 materials also depended on the precursors of bulk g-C3N4, following the order of apparent rate constants (kapp): dicyandiamide ＜ melamine ＜ urea ＜ thiourea. The improvement of adsorption ability in porous g-C3N4 are responsible for the high photocatalytic activity of porous g-C3N4. Moreover, the existence of sulfur in thiourea caused the different interaction in the preparation, resulting in a high activity. |
