Enhanced Sunlight-Driven Photocatalytic and Antibacterial Activities of Flower-Like ZnO@MoS₂ Nanocomposite

Here, flower-like ZnO@MoS₂ heterostructure (FZMH) has been successfully synthesized by a facile hydrothermal method within a short hydrothermal time of 12 h at an optimized ZnO nanosphere (ZNS) concentration of 24 mM. The morphological and structural characterisations of FZMH have confirmed the formation of nanosheet-based ordered FZMH. The photocatalytic dye degradation performances of as-synthesized samples have been tested by decolourisation of methylene blue (MB) dye under the sunlight irradiation, and it is observed that the FZMH shows the highest MB dye degradation efficiency of ~ 67% at time 2 h. The pseudo-first-order reaction rate constant (k) of FZMH is found to be of ~ 8.4 × 10⁻³ min⁻¹ which is 2.00 and 1.83 times higher than that of ZNSs and MoS₂ nanosheets (MNs), respectively. The antibacterial potentiality of ZNSs, MNs, and their nanocomposites on some Gram-positive and Gram-negative bacteria has been studied by well-known diffusion method. It is observed that among the different as-synthesized samples, FZMH has exhibited selective and superior antibiofilm activity against Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis of ~ 64, ~ 69 and ~ 84%, respectively. Hence, hydrothermally synthesized flower-like ZnO@MoS₂ heterostructure can be used as an efficient photocatalyst to degrade different harmful dyes in water under the sunlight irradiation and superior antimicrobial activities against Gram-positive and Gram-negative bacteria have been explored.