MoS ₂ –CdS Composite Photocatalyst for Dye Degradation: Enhanced Apparent Quantum Yield and Reduced Energy Consumption

Abstract This study investigates the visible light‐assisted photocatalytic degradation of rhodamine B (Rh B) dye using MoS 2 –CdS nanocomposite. Two crucial operational parameters, illumination time and the weight ratio of MoS 2 to CdS, are systematically examined. Approximately, 91.9% of Rh B solution with a concentration of 10 mg/L is degraded by the MoS 2 –CdS photocatalyst under 60 min of illumination, with a photocatalyst dosage of 0.5 g/L. The results are consistent with a pseudo‐first‐order kinetic model, wherein the degradation rate constant of CdS increases fourfold after amalgamation with MoS 2 . The formation of the composite with MoS 2 results in 1.72 times increase in the apparent quantum yield and 3.15 times decrease in the electrical energy consumption per order of CdS nanorods under similar experimental conditions. The investigation also comprehensively explores the reactive species responsible for Rh B degradation under visible light in the presence of MoS 2 –CdS photocatalyst. This analysis confirms that both hydroxyl and superoxide anion radicals play a dominant role in Rh B degradation. These findings underscore the potential practical applications of MoS 2 –CdS nanorods in eco‐friendly water treatment technologies, offering efficient and sustainable solutions to contemporary environmental challenges.