Improvement of methylene blue removal by La: ZnO / GO nanocomposites in the presence of ultrasound

In this study, Lanthanum doped Zinc oxide/graphene oxide (La: ZnO/GO) nanocomposites were investigated as an effective catalyst for the sonocatalysis of methylene blue solution. The (La: ZnO/GO) nanocomposites with different amounts of La3+ (3,6 and 9 atom%) were synthesized via a simple method( precipitation method ) and SEM & TEM image showed the presence of ZnO nanorods on the surface of graphene sheet. The presence of lanthanum was confirmed by EDX analysis. The sonocatalytic degradation of methylene blue dye was studied in the presence of ultrasound alone and also in the presence of nanocomposites prepared. The results showed that La: ZnO(3%)/GO sonocatalysts exhibit the highest methylene blue degradation efficiency. The effective factors on dye degradation in the presence of ultrasound were optimized and optimal values including 0.1 g catalyst dosage, 10 mg / L initial concentration of dye and 80 minutes contact time with a reaction rate constant of 0.0158 min-1 were obtained.