ZnS Nanomaterials with Hexagon and Pentagon Structures: Effect of Surfactants on Surface Morphology and Biosensing Application

Zinc sulfide nanomaterials (ZnS NMs) are widely used in many important technological applications, and the performance efficiency is determined by the nanostructure, size, and shape. This indicates that achieving a desirable surface architecture is pivotal for any application. One of the efficient and cost-effective techniques, the hydrothermal method, offers uniform size, specific shape, and bulk synthesis capability. This research deals with the preparation of ZnS NMs exhibiting unique surface structures such as spherical, nano-pentagon, and nano-hexagon shapes through employing different zinc precursors and surfactants. The obtained material’s crystal structure was classified as cubic sphalerite and exhibited high purity, as analyzed by XRD, SEM-EDX, TEM, and XPS. Furthermore, the synthesized ZnS NMs were tested for their shape-dependent biosensing application, such as specific antibacterial tests against routine human pathogens such as E. coli, K. pneumoniae, and S. aureus. Several antibacterial methods, such as bacterial colony plate count, growth inhibition analysis, and minimum inhibition concentration (MIC) measurements were carried out. The results confirmed that the antibacterial action in the method employed was dependent on three factors: the NM shape, concentration, and type/nature of bacteria. Especially, the prepared ZnS NMs exhibited excellent antibacterial sensing characteristics, as observed from the lower MIC values in the range of 15.6~250 µg/mL.