Efficient visible-light photocatalytic ozonation for dye degradation using Fe2O3/MoS2 nanocomposite

In this study, Fe2O3/MoS2 nanocomposite was fabricated by a simple method and utilized in the visible-light photocatalytic ozonation (PCO) process for the removal of a recalcitrant azo dye, Acid Blue 113. The process was analyzed and optimized by response surface methodology (RSM) based on Box-Behnken design (BBD). Maximum dye removal (99.0%) was achieved at pH = 6.4 using 20 mg of the nanocomposite, 0.2 g l(-1) h(-1) ozone flow, and 45 min. Application of the PCO process for the treatment of real textile wastewater revealed that the O-3/vis light/nanocomposite system is more efficient than the bare catalysts, ozone, and O-3/light systems. Kinetic study showed that the PCO process obeyed pseudo-first-order and Langmuir-Hinshelwood models. The as-synthesized Fe2O3/MoS2 nanocatalyst showed high stability in the PCO process with 92% dye degradation after eight repetitive cycles. The results show that the nanocatalyst comprising alpha-Fe2O3 nanoparticles and MoS2 nanosheets can be efficiently applied in the wastewater treatment by the PCO process.