Synthesis of Bi₂WO₆ photocatalyst modified by SDBS and photocatalytic performance under visible light

Bismuth tungstate (Bi₂WO₆) photocatalysts, which modified with different ratios of sodium dodecyl benzene sulfonate (SDBS) and with enhanced visible light-driven activity, were synthesized by a facile solvothermal process. The photocatalysts were characterized by X-ray diffraction, scanning electron and transmission electron microscopies, and X-ray photoelectron and ultraviolet–visible diffuse reflectance spectroscopies. SDBS addition was found to control particle morphology and improve photocatalytic activity of Bi₂WO₆ catalysts. The solvent-thermal reaction time was critical in determining the catalysts’ structures and shapes and optimal at 16 h. Photocatalytic activities of SDBS–Bi₂WO₆ were determined by photocatalytic degradation of tetracycline (TC) in aqueous solution under visible light irradiation. Optical properties and TC degradation tests showed these SDBS–Bi₂WO₆ catalysts to exhibit enhanced visible light-driven photodegradation for TC. The photocatalytic activity for TC degradation was maximized at 90.39% after 90 min at 1.0 wt% SDBS dosage. In addition, the possible mechanisms for catalyst formation and photocatalytic degradation were discussed.