Synthesis of Zinc Oxide/Activated Carbon Nano-Composites and Photodegradation of Rhodamine B

In this study, microemulsion and hydrothermal methods were used together to obtain controlled particle size and uniform distribution of zinc oxide/activated carbon nano-composite materials. Precursors of zinc oxide/activated carbon were prepared using a microemulsion of an oleic acid/n-Butanol/sodium hydroxide solution. Precursors were dispersed in water or ethanol and then treated, using a hydrothermal method to obtain zinc oxide/activated carbon. Samples were characterized using thermogravimetric/differential thermal analysis, scanning electron microscopy, energy dispersive spectroscopy, infrared spectroscopy, and X-ray diffraction. Scanning electron microscopy results indicated that zinc-oxide particles with a narrow size distribution were distributed evenly on the surface of the activated carbon. Infrared spectroscopy showed that peak zinc-oxide vibration bands shifted to lower wave numbers with a reduction in the concentration of zinc sulphate, an increase in the concentration of sodium hydroxide in the microemulsion, and a prolonging of the hydrothermal reaction time. Photodegradation rate of rhodamine B in aqueous solutions containing zinc oxide/activated carbon composites at a pH of 5 was remarkably faster than the rate in aqueous solutions containing nano-zinc oxide.