it was found that guanidine carbonate source (0.5, 1.0 and 2.0M)
shows the photocatalytic activity higher than urea source (0.5, 1.0 and 2.0M). As the guanidine carbonate
source, the photocatalytic activity could be degraded of MB aqueous solution to 80-85% in 1h under
visible light irradiation. The photocatalytic activity was increased with decreasing the concentration of
guanidine carbonate. In addition, the nitrogen-doped TiO2 powders without irradiation could decolorized
MB aqueous solution from 1×10-5M to