Quantum Mechanical Calculation of Graphene Oxide Nanosheet Prepared via Modified Hummer Method: Role in Dye Degradation and Antibacterial Activity

This paper reports the synthesis of graphene oxide nanosheet (GONS) through the modified Hummer’s method. The characterization was done by X-ray diffraction (XRD), UV-Visible, and Fourier transform infrared (FT-IR) spectroscopic methods. Scanning Electron Micrograph (SEM) was employed to study morphological features of the nanosheet showing the formation of firmly suspended GONS. The photocatalytic activity of the GONS was tested against methylene blue (MB) dye and 63% degradation was obtained in 60 minutes. The antibacterial activity was also tested against Bacillus subtilis (B. subtilis) and Escherichia coli (E. coli) with zone of inhibition values of 12±0 and 14±0.4 mm respectively. Through the density functional theory (DFT) calculations, important parameters like highest and lowest occupied molecular orbitals (HOMO and LUMO), absolute softness and hardness, etc. were calculated. The HOMO-LUMO difference was found to be 2.806 eV which was correlated with the bioactivity and stability of the nanosheet.