Green Chemistry Syntheses of Different Morphology Novel Nano-Sized Cobalt(II) Supramolecular: As a Precursor for the Synthesis of Cobalt(II) Oxide Nanoparticles, Thermal, Hirschfeld Surface Analysis and Biological Activities

Utilizing two distinct experimental techniques, the cobalt(II) metal-organic compound denoted as (Co-MOC), [Co(L)2(H2O)4], where L = pyridine-3-carboxylic acid) has been successfully synthesized: branched tube and sonochemical strategies. Notably, both methods yielded identical macro and nanostructures. Characterization of the nano compound involved the application of Scanning Electron Microscopy (SEM), Powder X-Ray Diffraction (PXRD), and Fourier Transform InfraRed (FT-IR) spectroscopy. Single-Crystal X-Ray Diffraction (SCXRD) analyses of compound Co-MOC revealed the coordination of Co2+ ions in a hexacoordinated environment. Furthermore, the scope of the investigation encompassed an in-depth examination of how various variables, such as temperature, reaction time, reactant concentration, and sonication energy, impact both the process of formation and the ultimate morphology of the compound synthesized through the sonochemical approach. Additionally, the research delved into an extensive exploration of diverse analytical methodologies. This included the application of techniques such as Thermal Gravimetric Analyses (TGA) and Differential Thermal Analyses (DTA) to elucidate changes in weight and temperature-driven behaviors within the samples. Moreover, compound Co-MOC underwent comprehensive scrutiny using Hirshfeld Surface Analysis (HAS) to unravel insights into its crystal packing and the intermolecular interactions present. Biological activity assessment involved testing the synthesized compounds against two bacterial strains:  gram-negative Escherichia coli (E. coli) and gram-positive Staphylococcus aureus (S. aureus). Notably, the compounds exhibited noteworthy antibacterial efficacy within a non-living environment.