Impact of Ultrasound Exposure on the Optical, Structural, and Antibacterial Properties of Graphene Oxide Nanosheets

This study investigates the effect of ultrasound exposure on the structural, optical, and antibacterial properties of graphene oxide (GO) nanosheets synthesized via a modified Hummers’ method. The exfoliation and functionalization of GO were analyzed using X-ray diffraction, Fourier transforms infrared spectroscopy, UV-Vis spectroscopy, and field emission scanning electron microscopy. XRD analysis confirmed a significant increase in interlayer spacing (from 0.337 nm to 0.909 nm) with increasing ultrasound exposure, indicating enhanced exfoliation. FTIR spectra revealed the incorporation of oxygen-containing functional groups (O–H, C = O, C–O, and C–O–C), which increased GO’s hydrophilicity and dispersion. UV-Vis spectroscopy demonstrated a redshift in the absorption peak (from 232.5 nm to 230 nm), signifying size reduction and enhanced suspension stability. FESEM images further confirmed the fragmentation and reduced lateral size of GO nanosheets. Antibacterial properties of GO demonstrated that GO was inhibition zones increased with the increase of GO concentration.