Rapid Photocatalytic Decolorization of Methyl Orange under Visible Light Using VS₄/Carbon Powder Nanocomposites

Photocatalytic decolorization of the dye compounds represents a promising approach for textile wastewater treatment, and thus, development of new photocatalysts will be of strong interest. Herein, a novel photocatalyst based on transition metal chalcogenides vanadium tetrasulfide (VS₄) was prepared via a simple one-step hydrothermal synthesis, and the synthesized VS₄/carbon powder nanocomposites exhibited excellent photocatalytic decolorization efficiency under visible light irradiation. A significantly high methyl orange (MO) decolorization rate of 13.4-19.8 mg L^-1 h^-1 was achieved. Reactive species such as •O₂^-, h⁺, and e^- generated through this photocatalytic process have played key roles in decolorization with phthalic acid as a product. The optimal catalyst dosage was determined to be 1.0 g L^-1. The decolorization rate was enhanced with the increase in initial MO concentration, and an acidic condition favored the degradation. The VS₄/carbon powder nanocomposites could maintain the MO decolorization efficiency above 90% in four consecutive reused cycles. The results of this study have collectively demonstrated a promising photocatalyst that encourages further investigation and development for dye decolorization in textile wastewater.