Diverse capability of chemically exfoliated 2D MoS₂ nanosheets for photocatalytic, adsorption and antibacterial applications supported by in silico molecular docking

2D MoS₂ nanosheets have been successfully synthesized by salt assisted exfoliation of bulk powder. The recorded X-ray diffraction pattern, high resolution transmission electron micrograph, selected area electron diffraction pattern, confirmed the hexagonal symmetry and exfoliation of bulk powder to nanosheets. Two absorption peaks observed at 643 nm and 701 nm in UV–Vis spectra correspond to direct band gap transitions. The lateral size and zeta potential of exfoliated nanosheets were found to be 340 nm and − 21.5 mV, respectively. The presence of Mo–O bonding and S = O functional groups on hexagonal structure was confirmed by the FTIR measurements. The decrease in the photoluminescence intensity of exfoliated MoS₂ nanosheets relative to bulk powder clearly support the quantum confinement effect and delay in electron–hole recombination. The X-ray photoelectron spectroscopy analysis confirms the characteristic peaks of Mo 3d, Mo 3p and S 2p, along with their respective binding energies. The specific surface area and pore size of exfoliated MoS₂ nanosheets evaluated from Brunauer–Emmett–Teller analysis were found to be 5.430 m² g⁻¹ and 1.802 nm, respectively. The two distinct Raman active characteristics peaks observed at 383.94 cm⁻¹ and 409.04 cm⁻¹ are associated with E¹_2g and A¹_g vibrational modes of MoS₂ hexagonal structure. The exfoliated 2D MoS₂ nanosheets were evaluated for their effectiveness in three environmental cleaning applications: (i) photocatalytic degradation of MB dye solution (ii) removal of As ions from water by adsorption and (iii) antibacterial potential. The photocatalytic results confirmed the degradation of 30 ppm MB dye solution with a degradation constant of 0.0431 min⁻¹ and 98% removal efficiency under sunlight exposure, which is attributed to generation of reactive oxygen species (ROS) on MoS₂ surface. The adsorption results showed that exfoliated MoS₂ nanosheets were found to be excellent As ions scavengers with adsorption capacity − 112.44 mg/g and follow pseudo second order kinematics. The antibacterial potential of synthesized 2D nano-structure were tested against one gram positive (Bacillus subtilis) and two gram negative (Escherichia coli and Pseudomonas aeruginosa) pathogenic strains. The biocidal mechanism of exfoliated MoS₂ nanosheets is supported by in silico molecular docking study on FTsZ protein of Bacillus subtilis, GGBD protein of Escherichia coli and LasR protein of Pseudomonas aeruginosa.