1, CINVESTAV-IPN, Mexico City, , Mexico
3, Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, , Mexico
4, Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Mexico City, , Mexico
5, Ingeniero Quimico Industrial, Escuela Superior de Ingeniería Química e Industrias Extractivas – IPN, Mexico City, , Mexico
6, Departamento de Ciencias Naturales, Universidad Technologica de Panama, Panama, , Panama
7, SEES, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, , Mexico
Photocatalytic disinfection of Escherichia coli K12 was experimented with the synthesized Graphene oxide/ Titania (GO/TiO2) semiconducting nanocomposites. GO was functionalized with TiO2 to increase efficiency in the disinfection process. Characterizations by scanning electron microscope (SEM) and transmission electron microscopy (TEM) for the surface morphology, X- ray diffraction (XRD) for the crystal structure, Raman spectroscopy for the structural analysis and UV-Vis diffuse reflectance (DR) to determine the band gap in GO/TiO2 semiconducting nanocomposites were carried out. The photocatalytic disinfection was performed under visible light irradiation using a solar simulator. For the study of reactive oxygen species (ROS) in the photocatalytic disinfection of Escherichia coli K12, scavenger study was done. From the XRD results, partial reduction of GO to reduced GO was observed due to the increase in the concentration of GO. The SEM analysis shows the homogeneous distribution of TiO2 nanoparticles over GO. According to Raman results, the corresponding D and G bands were identified at 1342 cm-1 and 1600 cm -1 respectively showing the crystalline quality of the synthesized nanocomposites. All these characterization techniques reveal the enhancement of photocatalytic disinfection by embedding TiO2 nanoparticles in GO. As a result, the electron – hole pair recombination rate was reduced, and photocatalytic inactivation efficiency was increased. ROS, which is responsible for disinfection was identified.