Chromium Oxide Nanoparticles via Green Synthesis: Investigating Photocatalytic and Antimicrobial Properties Using Molecular Docking and Hirshfeld Surface Analysis

Abstract

A facile strategy was used for the synthesis of chromium oxide nanoparticles using leaf extract of Tinospora cordifolia via sol–gel auto combustion method and its photocatalytic performance was observed. The green synthesized Cr₂O₃ nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), EDAX, UV–Vis spectroscopy, transmission electron microscopy (TEM), selected area electron diffraction (SAED), and photoluminescence (PL). XRD pattern confirmed the purity of Cr₂O₃ nanoparticles. The SEM images showed porosity of Cr₂O₃ NPs. The band gap, as determined using UV–visible spectra, was measured to be 3.41 eV. TEM images revealed the crystalline shape and size of the nanoparticles. The PL spectra showed the emission peak at around 465 nm. In this study, inter-molecular interactions were examined using Hirshfeld surface analysis. The green synthesized Cr₂O₃ nanoparticles exhibit photodegradation efficiency up to 89.74% against malachite green dye after 25 min of UV irradiation. This investigation assessed the antimicrobial properties of Cr₂O₃ nanoparticles synthesized via a green route using Tinospora cordifolia leaf extract. The results revealed significant antibacterial activity against a panel of microorganisms, including Gram-positive Staphylococcus sp., Bacillus sp., and Gram-negative bacteria (Klebsiella sp., E. coli), as well as potent antifungal activity against Aspergillus niger. Further, the interaction of Cr₂O₃ with key protein targets, FtsZ and DHFR, was evaluated using Autodock Vina. The molecular docking results indicated a strong binding affinity of Cr₂O₃ to the active sites of both FtsZ and DHFR proteins, with a docking score of − 2.66 and − 2.84, respectively.