Eco-Friendly CuMoO₄/Bi₂S₃ Nanocomposites: Superior Solar-Light Catalysts for Indigo Carmine Dye Degradation and Its Antibacterial Efficacy

In this study, Bi₂S₃, CuMoO₄, and a novel CuMoO₄/Bi₂S₃ nanocomposite were successfully synthesized via a straightforward solvothermal and hydrothermal method. The resulting nanocomposites underwent comprehensive characterization utilizing XRD, FTIR, XPS, TEM, and UV-vis DRS techniques to elucidate their structural, chemical, morphological, and optical properties. Furthermore, the photocatalytic performance of Bi₂S₃, CuMoO₄, and the CuMoO₄/Bi₂S₃ nanocomposite was evaluated through the degradation of Indigo carmine dye (IC) under solar light irradiation. Remarkably, the CuMoO₄/Bi₂S₃ nanocomposite displayed significantly enhanced photocatalytic efficiency compared to individual Bi₂S₃ and CuMoO₄ counterparts. The CuMoO₄/Bi₂S₃ heterojunction reduces electron–hole (e^––h⁺) recombination and enhances visible light absorption, significantly improving photocatalytic degradation. Under solar light, CuMoO₄/Bi₂S₃ achieves 98% degradation efficiency, surpassing Bi₂S₃ (46%) and CuMoO₄ (53%). The investigation into photodegradation kinetics revealed adherence to the pseudo-first-order model, with the CuMoO₄/Bi₂S₃ nanocomposite demonstrating a larger rate constant than Bi₂S₃ and CuMoO₄, affirming its superior photocatalytic activity. Additionally, the photostability of the CuMoO₄/Bi₂S₃ nanocomposite was explored, and a plausible photocatalytic mechanism was proposed. The antibacterial activity was tested against Staphylococcus aureus (S.aureus) and Escherichia coli (E.coli). The findings suggest promising ways for employing these composite materials in various environmental remediation and energy conversion applications.