Sol–Gel-Derived TiO₂ and TiO₂/Cu Nanoparticles: Synthesis, Characterization, and Antibacterial Efficacy

Abstract

This study reports on the antibacterial efficacy of both the TiO₂ and TiO₂/Cu nanoparticles prepared through the sol-gel method. The materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and Brunauer-Emmett-Teller (BET) analysis. The SEM and TEM showed the spherical morphology of the nanoparticles, while EDX and XPS confirmed the incorporation of Cu into the TiO₂ nanoparticles. The XRD confirmed the formation of the tetragonal anatase phase of TiO₂/Cu while the FTIR revealed the functional groups linked to the doped TiO₂ nanoparticles. The thermal stability of TiO₂/Cu was found to be lower than pure TiO₂. Moreover, TiO₂ and the doped TiO₂ nanoparticles were notably effective against <i>Bacillus subtilis</i><i>(</i><i>B. subtilis</i><i>) and</i><i>Escherichia coli</i>(<i>E. coli</i>); however, the addition of Cu to TiO₂ did not have any effect on the antibacterial activity probably due to the lower weight content in the composites. Interestingly, the antibacterial efficiency was determined to be 90 and 80% against <i>B. subtilis</i> and <i>E. coli</i>, respectively.