Structural, Morphological and Antibacterial Studies of Solvothermally Synthesized ZnS Nanostructures: Effects of Sulphur Precursors

Abstract

The study of zinc sulphide semiconducting nanostructures for antibacterial applications is widely increasing. As the treatment of many infectious diseases is still challenging and efforts are being made to control the growth of bacterial infection. The present work focuses on the structural, morphological, elemental, optical and antibacterial studies of zinc sulphide (ZnS) semiconducting nanostructures synthesized using different sulphur sources. Solvothermal method is used as it is one of the most promising methods to synthesize nanostructures by controlling the reaction time and reaction temperature under high pressure. The X-ray diffraction (XRD) results give the zinc blende crystal structure for both ZnS nanostructures with crystallite size lies in the range 3 to 4nm. The prominent change in the morphology of the synthesized nanostructures is shown by scanning electron microscopy (SEM). Energy dispersive X-ray spectroscopy (EDX) provides information regarding the elemental framework and type of chemical bonding present is as done by Fourier transform infrared spectroscopy (FTIR). The luminescence and bandgap determination are done by photoluminescence (PL) spectroscopy and UV-visible absorption spectroscopy. The synthesized nanostructures are efficient in the degradation of the cell membrane of Escherichia coli (E. coli.) and Staphylococcus aureus (S. aureus) bacterial families. The production of reactive oxygen species (ROS) is the dominating mechanism of action responsible for the degradation of cell membrane causing cell death. They may be further used for other applications such as an antioxidant and photo catalytic degradation etc.