Ternary Carbon Spheres/PAA-Al₂O₃ Nanoparticles as an Efficient Catalyst for RhB Dye Degrader and Bactericidal Agent; Molecular Docking Analysis

Ternary CSs/PAA-Al₂O₃ NPs (carbon spheres/polyacrylic acid-aluminum oxide nanoparticles) were prepared using the sol-gel method. The main purpose of the current investigation is to increase the catalytic and antibacterial performance of CSs/PAA-doped Al₂O₃ NPs. PAA and CSs are used as doping agents as they increase the charge kinetics by reducing the e⁻/h⁺ pair recombination rate of Al₂O₃. The as-prepared samples were examined using X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV-vis spectra. According to the XRD pattern, Al₂O₃ was crystalline with orthorhombic structure and measured crystallite size was found to be decreased upon doping. Conversely, dopants effectively increased the band gap energy from 5.09 to 5.25 eV of prepared samples. Nanoparticles were observed in the TEM micrographs and particle size decreases with the incorporation of dopants. The experimental findings proved that the CSs doped specimens provided better catalytic and antibacterial activity than binary ones (PAA- Al₂O₃) and pure Al₂O₃. 4% CSs/PAA-Al₂O₃ demonstrated a maximal degradation 86.3% (neutral medium) 83.3% (acidic and basic environments) within eight min. 4% CSs/PAA-Al₂O₃ revealed the inhibitory diameter against E. coli was about 9.15 ± 0.02 mm. Furthermore, in silico molecular docking studies verified the postulated microbicidal mechanism, which showed that these nanostructures may block the enzymes FabH and FabI responsible for the fatty acid pathway.