Preparation of controlled-shape ZnS microcrystals and photocatalytic property

ZnS microcrystals with various shapes, including polyhedron, fan-shaped sheet, hexagonal rectangle and missing angle rectangle, were successfully prepared using a simple hydrothermal method by changing the experimental conditions. The as-obtained ZnS samples were characterized by X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The photocatalytic activities of the ZnS microcrystals with different morphologies were investigated by degradation testing of methylene blue aqueous solution. The highest photodegradation rate of methylene blue over the polyhedron-shaped ZnS reached up to almost 100%. The photodegradation efficiencies under various conditions, including amount of catalyst, pH of aqueous solution and initial concentration of methylene blue, were studied in the presence of polyhedron-shaped ZnS. The polyhedron-shaped ZnS microcrystal can thus be utilized as a promising photocatalyst for photodegrading dyes in wastewater treatment.