Figure 3.

Spectrum of adsorption of MG solution in the presence of (a) CdS; (b) CdS-TiO₂; (c) CdS-C₆₀; and (d) CdS-C₆₀/TiO₂ under different irradiation times when exposed to halogen tungsten lamp. For A–G, each absorbance spectrum was recorded over a 5 min interval; for G–J, each absorbance spectrum was recorded over a 10 min interval; for J–L, each absorbance spectrum was recorded over a 30 min interval with visible light illumination. (e) Absorbance variations as a function of irradiation time (f), ln (c₀/c), and the linear of control for P25, CdS, CdS-C₆₀, CdS-TiO₂, CdS-C₆₀/TiO₂ in MG deterioration after 120 min exposure to radiation at ambient temperature. [MG] = 4 mg/L; [P25] (CdS, CdS-C₆₀, CdS-TiO₂, CdS-C₆₀/TiO₂) = 0.6 g/L.