Sonochemical synthesis of holmium doped zinc oxide nanoparticles: Characterization, sonocatalysis of reactive orange 29 and kinetic study

The sonochemically synthesized Ho-doped ZnO nanoparticles were characterized by XRD, SEM, TEM, and XPS techniques. The sonocatalytic degradation of Reactive Orange 29 (RO29) was greater than that with sonolysis alone. DE% declines with the addition of chloride, carbonate, sulfate, and tert-butanol as radical scavengers. Addition of potassium periodate, peroxydisulfate, and hydrogen peroxide as enhancers improves DE%. The results demonstrate proper reusability of the doped sonocatalyst. Degradation intermediates were identified by gas chromatography-mass spectrometry (GC-MS). Using nonlinear regression analysis, an empirical kinetic model was developed to predict the pseudo-first-order constants (k_app) as a function of the operational parameters.