Fig. 7

(a) Variation of percent removal as a function of contact time at different initial MB concentrations (5–15 mg/L) at pH 9.0 and 10.0 mg CuO-NPs, (b) Effect of the photocatalyst dose on the removal efficiency of MB (50 ml MB solution (10 mg/L), Temp. = 25 ˚C and pH 9.0).