Optimized AgBr/PVP-Fe₂O₃ Nanostructures for Effective Catalytic and Biological Activities; Computational Insights

Ternary heterostructures AgBr/PVP-Fe₂O₃ NSs (silver bromide/polyvinylpyrrolidone-iron oxide nanostructures) were developed using low temperature and facile approach. The developed system contained PVP overlapped multiple-shaped structures of Fe₂O₃ interlinked with AgBr nanorods. The ternary system was used for effective wastewater treatment and bactericidal inactivation with molecular docking analysis. This research covers experimental as well as computational validation for antibacterial activity. AgBr and PVP provide more active sites, charge transfer efficacy, and structural and chemical stability to Fe₂O₃. Comprehensive structural, morphological, elemental, and optical characterizations were assessed to determine the impact of PVP and AgBr on Fe₂O₃. XRD analysis revealed the monoclinic and hexagonal structure of Fe₂O₃ with decreased crystallite size from 61.80 to 50.52 nm upon PVP and AgBr doping. SAED analysis showed the polycrystalline behavior of Fe₂O₃ and doped Fe₂O₃. UV-Vis spectroscopy displayed a blue shift with PVP and AgBr, indicating increased band gap energy value for AgBr/PVP-Fe₂O₃. The mode of stretching vibration at 576 cm^{− 1} corresponding to Fe₂O₃ was affirmed by FTIR spectra and shifting towards a lower wavenumber was observed with the addition of PVP and AgBr. The optimized sample (4% AgBr/PVP-Fe₂O₃) showed significant rhodamine B reduction efficacy (85.33%) as well as a better inhibition zone (3.10 ± 0.03 mm) towards MDR E. coli. Microbicidal analysis aside, an in-silico docking research of E. coli showed that AgBr/PVP-Fe₂O₃ had a binding value of 7.05 for dihydrofolate reductase (DHFR) and 8.90 for dihydropteroate synthase (DHPS).