Catalytic evaluation and in vitro bacterial inactivation of graphitic carbon nitride/carbon sphere doped bismuth oxide quantum dots with evidential in silico analysis

Abstract

Herein, Bi₂O₃ quantum dots (QDs) have been synthesized and doped with various concentrations of graphitic carbon nitride (g-C₃N₄) and a fixed amount of carbon spheres (CS) using a co-precipitation technique. XRD analysis confirmed the presence of monoclinic structure along the space group P2₁/c and C2/c. Various functional groups and characteristic peaks of (Bi–O) were identified using FTIR spectra. QDs morphology of Bi₂O₃ showed agglomeration with higher amounts of g-C₃N₄ by TEM analysis. HR-TEM determined the variation in the d-spacing which increased with increasing dopants. These doping agents were employed to reduce the exciting recombination rate of Bi₂O₃ QDs by providing more active sites which enhance antibacterial activity. Notably, (6 wt%) g-C₃N₄/CS-doped Bi₂O₃ exhibited considerable antimicrobial potential in opposition to E. coli at higher values of concentrations relative to ciprofloxacin. The (3 wt%) g-C₃N₄/CS-doped Bi₂O₃ exhibits the highest catalytic potential (97.67%) against RhB in a neutral medium. The compound g-C₃N₄/CS-Bi₂O₃ has been suggested as a potential inhibitor of β-lactamase_E. coli and DNA gyrase_E. coli based on the findings of a molecular docking study that was in better agreement with in vitro bactericidal activity.